Man Made Fibres Conference - Dornbirn Austria Sept 2011

Introduction

740 delegates from 30 countries were drawn to Dornbirn for this, the 50th annual conference organised by the Austrian Man-Made Fibres Association.  Germany provided most delegates (264) and with Austria (192) and Switzerland (102) the majority language was German.  There were 3 simultaneous sessions so a maximum of a third of the total could be heard. Several were not available in hard copy and more than usual were available only in German.  The tight scheduling left little time for questions.

Opening Address

Friedrich Weninger CEO Lenzing and President of AMFA noted that in 1962 the first AMFA conference recorded a world fibre production of 15 million tonnes, 0.7 million being synthetic and 10.1 million cotton.  Last year the total had reached 73 million tonnes, 43 million being synthetic,  25 million being cotton and man-made cellulosics had reached a record 4.2 million tonnes.  Continued growth of the total fibre market was expected to be 3% per annum, with cotton having plateaued and man-made cellulosics due to grow fastest at 9% pa.

Predicting short term trends was trickier than ever:

·         The stock market fluctuations were caused by speculation unbacked by real effects

·         Customers did not really know what they wanted and could do no more than extrapolate from past trends.

Megatrends were easier:

·         The future would be dominated by developments related to energy supply, healthcare, biotechnology, sustainability, well-being and the convenience of nonwoven materials.

·         Nonwovens would grow to consume 25% of total fibres. (with 100 million tonnes fibres expected to be used by 2020, this equates to 25 million tonnes of nonwovens)

·         Total Technical Textiles (including NWs) would be half the total.

·         Wood will remain the most important, but not the only source of cellulose for fibre.  Waste biomass sources were being developed.

The Physics of Economics

Michael Harder of the Office of Interdisciplinary Sciences (Germany) argued the case for using the developing science of complex systems to help understand the interactions now occurring in the financial system.  In a most thought-provoking presentation he showed how the new science can explain the inter-connectedness of the current crises of debt, inflation, population movements, and poverty and suggested the need for massive changes in the way we work, our currencies, production methods and Eurozone politics.  Along the way, the following points were notable:

·         Modern physics suggests the world comprises logical “islands” in an ocean of chaos and probability.  We prefer the logical and believe in causality, which leads to specialization. 

·         Specialists don’t recognize the wider reality.  They feel their island is the only correct one,  whereas many correct islands must be connected to perceive reality. This requires more complex thinking than we’re used to.

·         Order and Chaos are the key “attractors” with entropy leading to chaos and action leading to order. 

·         Ordered systems tend to deteriorate into chaotic systems and the chaotic tends to order.  The result is a natural balance best described by Darwinism.

·         “Darwinism is essential for any company management.”

However, reward of the fittest eventually leads to a growing population hitting system boundaries where the favoured species runs into the limits of its environment and risks crashing if it fails to correct its growth and adapt. (“Don’t try to work against nature”)

The global economy hit its system boundary about 25 years ago when we started consuming more resources than the planet could sustainably provide.  It is now working against nature and committing four elementary errors:

1.    Growth is at the centre of society with all else subservient.  This is an unsustainable social philosophy.  Man used to be at the centre of the system with economics as one of his tools.  This was sustainable.

2.    The biosphere is limited but the demands of economic growth assume it’s unlimited.  Physics and Darwinism show that a system crash is the consequence of not adapting to the limit.  Further economic growth is now at the expense of over-exploitation of natural resources, the labour force, and family life.  Depletion of resources, unemployment, rising debt, family disintegration and demographic catastrophe are components of the system crash that is now becoming evident.

3.    In the last 30 years, Money Supply has grown ahead the value of goods produced by a factor of 10 and the resulting excess liquidity has fuelled speculative and complex financial dealings which appeared to offer greater wealth.  Sustaining this financial system and its compound interest requires exponential growth of the money supply which is impossible.  Paradox of Systemic Importance: as important participants in the system crash, any attempt at their rescue guarantees the future crash of the whole system.

4.    The Eurozone: Game theory simulations show that systems with multiple parties only work if all can defend their territory with their individual strength.  If a party is too strong or too weak and no correction is possible then a complete system crash is inevitable.  A correction was defined as war, devaluation, bankruptcy or game-exit.

In conclusion, Dr Harder argued the case for developing a new economic system now that we have hit the system boundaries.  The old one was fine and worked well up to about 30 years ago.  Unfortunately there do not appear to be any politicians capable of taking this task on board, so the future will be stormy.  Prepare for the period after the storm: you will be on a very different sea.

Politics and Man-Made Fibres

Andreas Eule of CIRFS, the EU Man-Made Fibres Association observed that fibre production is more energy and labour intensive than the chemicals industry and so needs to be particularly innovative if it is to survive in Europe.  China's labour costs are about one-tenth of the EU's and while these are now moving above €3/hour, EU rates are rising faster so the gap is now widening.  China's energy costs about half that of Germany/Italy; 33% of the German cost being tax.  On top of this the new eco-taxes will drive more manufacturing to the East with many more jobs being lost in the EU.  Mr Eule commented that environmental policies were pure trial and error with no-one being able to predict the final results.  EU environment bureaucracy is massive with 50 different offices in 21 ministries dealing with the 11 major environmental objectives.  The EU is blaming the national governments for lack of progress and vice versa, the result being that industry is being choked by the politics.  Within the EU 27, 75% of laws are now based on EU central law and this is moving to 100%.  Sure, nations have an input but the resulting legislation is always a compromise to suit 27 different countries.  Intentions are good but the results are again "trial and error".

MMF growth rates globally should be about 4.5% pa, with cotton managing a 2% rate.  However China was planning to add 30% to its already enormous capacity in the next 5 years.  Massive overcapacity will result.

In conclusion, the EU must not end up depending on Asian textiles alone.  It needs its fibre producers to feed its garment supply chain, but the fibre producers have to learn to export more to survive.

Fibre Demand – the next 50 years

Peter Driscoll of PCI Fibres and Raw Materials (UK) assumed the existing range of fibres would still be used in 2060 (no new polymers) but their properties would have improved. The key market trends would be as follows:

·         Global consumption of all fibres had reached 11 kg/capita in 2010, similar to the pre-recession figure in 2007.

·         The 88-94 stagnant period was due entirely to reduced cotton demand resulting from a swing to the “filament look” in fashion textiles.

·         Cotton consumption will increase from 3.6 to 4.0 kg/capita by 2020 and remain roughly at this level to 2060.  However due to the population increase demand will reach 31 million tonnes by 2020 and 41 million tonnes by 2060.

·         The so-called Cellulose Gap which is thought to be arising as a result of cotton’s inability to increase production is a myth.  Supply will increase in line with demand due mainly to the development of saline tolerant varieties and further yield increases.

·         MMF demand will rise from 6.7 to 8.5 kg/capita by 2020 and move on to 10.3 kgs/c by 2060. This is equivalent to a rise from 50 million tonnes now to 62 million in 2020 and on to 100 million tonnes in 2060.

·         Growth in MMF demand, 11% last year due to a massive Chinese “bubble” will fall to 7% until 2020 and then stabilise at 1.4%.

·         Cotton’s share of the market fell from 37% in 2000 to 33% in 2010, but will stabilise at 30% through to 2060.

·         MMF demand in the “Anglophone” developed world (12-13% of the global market) fell from a peak of 20 kgs/c in 2007 to 15 kgs/c in 2009 before recovering to 17 kgs/c in 2010.  It is unlikely to reach 20kg again before 2030.

·         China has 41% of global MMF market and its apparent MMF demand is now the same as the Anglophone region, peaking at 18kgs/c in 2016, and declining to 16kgs by 2045.  Here the apparent demand is increased by investment for exports, but China’s population will decline from 2020.

·         Greater Europe has 20% of the market and now uses 11 kgs/c of MMF’s.  Growth will be in Turkey and Eastern Europe and the percapita consumption should reach 18 kgs by 2060.

·         India’s share will grow from 6% to 13% by 2060, the percapita consumption rising from 2.5-7.5kgs, with cotton being favoured.

·         In the Far East (excluding China and South Asia) investment for export stopped in the mid-nineties and consumption of MMF’s has been stable at 11kg/c and will remain at this level through 2020, before rising steadily to 15 kgs by 2060.  It’s share of the global market will decline from 5% now to 3% by 2060.

·         South Asia’s demand (excludes India) for MMF would grow from 6% of the world total to 12% by 2060.  Percapita consumption rises steadily from 3 to 8kgs.

·         The developing nations will benefit from powerful population growth (“poverty and fertility go together”) so their share of global MMF’s will increase from 10% to 22% by 2060 despite percapita consumption rising from 3 to only 6kgs by 2060.

·         Apparel’s share of MMF would decline, technical uses would increase and household textiles would remain roughly constant.

·         Apparel and Home Textiles will benefit from an ample supply of cotton which when added to the MMF tonnage means these sectors will account for 80% of total useage by 2060, 36% of the total being cotton.

·         Overall, China will remain the centre of fibre and textile production, filament yarns will increase over spun-yarns and spunlaid nonwovens will continue to take share from carded.

·         The spunlaid nonwovens share of the global market will rise from 4% to 10% by 2060, and within this category, polyester will grow from 20% to 60%.

·         Polyester staple’s share of consumption will decline from 26% to 25% by 2060 due in part to the strength of cotton supply, the weakness of Chinese polyester consumption and the growth of spunlaid polyester nonwovens.

·         Polyester filament fabrics (including nonwovens) will grow from 46.6% to 52.1% of the global MMF market by 2060.

·         By 2060 Mr Driscoll expects fashion textiles to be consuming exotic spun-laid polyester nonwovens as well as knits and wovens.

Cellulosics in 2020

Dieter Eichinger of Lenzing (Austria) thought we should drop the words viscose and lyocell and refer to MMCF’s in future.  By 2020, Man Made Cellulosic Fibres would account for 10% of the 100 million tonne global fibre market the drivers being the increased use of all fibres per capita and the need for MMFC’s to fill the gap left by cotton’s inability to expand much further.  CAGR’s for cotton and MMFC’s were put at 1.3 and 9.1% respectively and cotton use in technical textiles where comfort is not required will have to cease to fill the 5.2% gap left over after the MMFC expansion.  All the familiar environmental arguments in favour of Tencel over cotton were revisited and superiority of MMFC’s in the latest low-energy Murata and Rieter air-jet yarn spinning systems was emphasised. Other claims for Tencel’s advantages were:

·         Improved sleep quality due to better moisture management by Tencel in bed-linen and pillow fillings.

·         Reduces bacteria, mold and mites by maintaining a drier climate.

·         Cooler workwear fabrics.

·         Good for the skin with Tencel®Sun offering UV protection and Tencel®C using chitosan for skin repair.

Click here for Tencel Development History

Future trends in Japan

Tsunehiro Ogawa of the Japanese Man-Made Fibres Association described 2011 as the year we recovered from the recession.  80 million tonnes of fibres would be used, 4 million of these being man-made cellulosics.  Operating rates were up to 82% from the recent low of 72.5% and both China and India were showing high growth rates.  World totals would grow from 51million tonnes in 2009 to 64 million in 2015 when polyester filament capacity would reach 34 million tonnes and polyester staple 21 million tonnes.  China's 5 year plan showed that they would further increase rayon fibre capacity from the 2009 level of 1.5 million tonnes to 3.3 million by 2015.  Overall China will produce twice as much fibre as it needs internally so will have about 20 million tonnes for export.

Global oversupply was anticipated with a supply-demand gap of 15-20% by 2014.

Strategy for the future?

Heinz Meierkord of Advansa Marketing (Germany) was critical of the EU policy:

·         “Free trade” was one-sided, unfair practices being accepted from non-EU members.

·         The focus was too short-term.

·         Domestic production was over-regulated but imports were less well controlled.  All suppliers should have to abide by the same rules

·         The way out of debt was to make more products for export.  €1 invested in manufacturing yields €1.40 of value.  €1 in banking yields 48c value.

·         There was a conflict of interest between the commodity and speciality value chains.  (Commodity products are dominated by retailers who destroy value.)

Worldwide patents grew 26%  in 2008 and then declined by 4.5% in 2009 as companies moved to reduce costs.  However Chinese patents filed at the EPO increased by 54% in 2009.  Patents are worthwhile if they can be enforced and product patents are easier to enforce than process patents.  Without enforcement patents give away technology, and the development of strong brands can afford better protection.

Our biggest challenge is demographics. Western population is ageing and our key competitors (China, India, Turkey...) have a young population with growing wealth and economic power.  For instance, the German workforce is forecast to decline from 44.6million to 38.1 million by 2025.  Furthermore, people buy less as they get older, ignore branding and go for higher value.  It’s the young who drive the economy.

PLA Update

Eamonn Tighe of Natureworks LLC (USA) claimed 100,000 tonnes/year sales of the Ingeo® PLA polymer into 40 different applications.  This is all made from US corn via dextrose, but the next plant – which will be in China and starting up in 2015 – will use cassava starch and sugar cane feedstock.  Longer term, and possibly in Europe, the third plant will convert cellulose from waste biomass via biorefineries now being developed with US government support.  A feedstock evolution slide showed 300 million lbs of dextrose from corn being used up to 2015 when a further 300 million lbs of dextrose from cassava and sugar cane would be added.  Between about 2020 and 2040 a further 800 million lbs of cellulose-based feedstock would be added bringing the total capacity to 1400 million lbs in 2040.

3 new nonwoven applications were illustrated.  A dust bag for vacuum cleaners from Electolux, a Duracover ground sheet from Bonar, and the GroVia BioDiaper (www.gro-via.com)

Since 2008, PLA resin prices had been stable compared with PET and were now below the synthetic.  Only 0.1% of the US corn crop or 0.04% of world corn is used to make Ingeo®.  Natureworks are now planning to get cradle to cradle certification for the resin on the basis that Ingeo biodegrades (or can be hydrolysed) into nutrients which feed microorganisms.

PLA Microfibres

Roy Dolmans of Aachen University (RWTH – Germany) has been spinning continuous filaments of PLA down to 0.5 dtex/fil and bulking them.  These yarns are now of interest in microfiber wipes because PLA resin prices are down below €2.5/kg.  He uses a 72 hole spinnerette with 0.13 mm holes and has to dry the resin from 530 down to below 50ppm of water before extrusion.  Diffusers rather than quenching is used to stabilise spinning and wind-up speeds of 3500m/min have been achieved.  Attempts at texturising suggest the frictional properties of PLA are a problem requiring some finish development.  Asked if the friction issue had anything to do with thermal stability, Dr Dolmans said that like PP, PLA was stable to 170^oC, but it could not yet be processed on commercial continuous filament systems.  More R&D was required.

The M&S customers view of Sustainability.

Mark Sumner of Marks and Spencer (UK) quipped that their 21 million customers have 21 million different views on sustainability. Summarising, they equate sustainability with:

·         Purity, morals and ethics and would want to be sure the products were safe and involved no child-labour anywhere in the supply chain.

·         Sustainable products would be "natural" and not "man-made"

·         Common sense sustainability involved recyling after use.

·         Legacy:  what are we leaving for the kids to deal with?

·         Will there be enough water?

Consumers fall into 2 groups, the Carers and the Apathetic. The former take positive steps to recycle and reduce energy use while the latter feel no individual can possibly have any effect on such an enormous problem.  M&S customers are biased to the former attitude:

·         26% of UK consumers are in the "not my problem" category, but only 19% of these are M&S customers.

·         28% of UK consumers will be sustainable "if its easy": 35% of M&S customers are in this group.

·         8% of UK consumers are "crusaders" for sustainability.  10% of M&S customers are crusaders.

The biggest single issue against buying sustainables appears to be the premium price.  The market really needs to see sustainability reducing costs not increasing them.  However in apparent contradiction of this, the recession has improved the demand for sustainables.  Once again we see expressed intentions differing from actual actions.

On a ranking of all factors affecting choice of clothing, the first of the sustainability criteria comes 7th.  Nevertheless consumers are paying attention to issues and thanks to the social media they will find out the facts about the clothing supply chain.  LCA data cannot be hidden behind misleading marketing and the supply chain is having to change to deal with this.  Traceability will be a key issue.  Known "hot-spots" being dealt with include the effect of intensive cotton farming on water quality and the animal welfare aspects of wool production.  M&S will always adopt best practice.  As a result we will see them using more recycled fibres (bottle polyester), more fibres with excellent environmental credentials (“Tencel - one of the most sustainable fibres available"), more fair trade products and more BCI fabrics (Better Cotton Initiative).  There will be incentives for returning used clothes to Oxfam.

Since starting their sustainability initiative, there have been no additional costs: in fact savings now  amount to £70million.

Biomass for food, raw materials and energy?

Martin Kaltschmidt of Hamburg Technical University noted that agricultural land was limited and in demand for:

·         Food crops to feed the growing population, and a trend to consume more meat in the East.

·         Conversion to lower yielding organic farming.

·         Nature conservation areas.

·         Biomass to feed the timber, pulp and paper industries in the emerging economies.

·         Biomass fibres – cotton, linen, flax etc.

·         Energy production either direct from burning biomass or via conversion to alcohols.

His figures for paper production showed demand rising from about 400 million tonnes per annum in 2010 to 500 mtpa in 2020, due mainly to 4.1%pa growth outside the EU, NA and Japan. Ignoring the peaks and troughs, cotton production had risen linearly from 10 mtpa in 1961 to 26 mtpa this year and looked set to rise further.  (World fibre demand for 2020 was shown as 100 mtpa based on Cotton Council figures.)  However the land area under cotton had been constant since 1961 with all the growth being met by yield increases. 

Overall, Dr Kaltschmidt thought biomass production would be able to expand to meet the needs given:

·         Increasing the total land area used to grow biomass. 

·         Recovering marginal or degraded land.

·         Increasing the yields.

·         Biomass was used more efficiently in large bio-refineries producing many materials.

·         Increasing R&D on biorefining.

·         Global trade to minimize local shortages.

Sustainability must consider the whole chain

Arturo Andreoni of Radici Group (Italy) displayed the well known EU Plastics Group LCA's which showed Nylon 6 and 66 to be the worst fibres for the environment.  Being major producers of nylon and fully vertical from phenol they've used the Simapro 7 software to do their own cradle-gate LCA which needless to say comes out a lot better.  Recycling improves matters further and if energy requirements are expressed as MJ per unit of fibre tenacity and not per kilo, then nylon proves superior to PP and LDPE.

Low Carbon-Footprint Polyester

Jürgen Musch of Advansa Marketing (Germany) saw the provision of enough food and water for the expected 2 billion increase in population between now and 2050 as the main challenge for mankind.  1 billion people were already starving, food prices were soaring yet grain continued to be converted into ethanol for transport.  Meat was now on the menu for many more people, and this required 10 times the water input c.f. wheat.

The “natural = good, synthetic = bad” wisdom had to be challenged.  Polyester provides 40% of the world’s fibre needs but uses less than 1% of the oil and a negligible amount of water – unlike cotton.  Its use requires far less energy than cotton over its useful life because it washes at lower temperatures and is very easy to dry.

The low CF polyester of the title is made from recycled bottle polyester, and a cradle to gate LCA by TNO (Netherlands) showed this to have:

·         a Global Warming Potential of 1042 kgs CO₂ equivalent per ton, i.e. between viscose and lyocell (Austrian production)

·         a Non-Renewable energy use of 19 GJ/tonne, i.e. between viscose and cotton.

·         A water use of 46 tonnes/tonne i.e. about 1/10^th viscose and 1/100^th cotton.

·         A land requirement of 1/300^th that of cotton, 1/90^th that of lyocell, and 1/70^th that of PLA.

Green Chemistry

Robert Peoples of the American Chemical Society Green Chemistry Institute said Green chemistry will play the central role in transforming chemistry from a petroleum based, take-and-make-waste enterprise, to one driven by the 12 principles of green chemistry and engineering.  Chemicals and processes will be chosen to be benign by design and informed by materials made by nature. Building blocks derived from renewable resources, and designed for degradation will be the polymers of choice in the future.  Pike Research was predicting the market for Green Chemicals to rise from less than $2bn this year to $100bn by 2020 making the production of these chemicals an enormous growth opportunity.  Biomimetics would be key to this growth.  Examples of products included:

·         Adhesives from soy mimicking the adhesive used by mussels.

·         Van der Waals adhesion, as used by geckos to walk on walls, from self-cleaning ultra high surface area films.

·         1-3 propanediol from fermentation of starch and sugar.  E.g. DuPont’s Sorona® monomer.

·         Hollow keratin fibres from chicken feathers in composites (e.g. printed circuits being developed for Intel)

Cellulose Solvents Compared

Denis Ingildeev of ITCF Denkendorf (Germany) compared NMMO with ionic liquids and commenced by describing NMMO as an intramolecular ionic liquid.  NMMO being solid at room temperature requires some water along with extreme temperatures and pressures to get cellulose into solution, whereas the true ionic liquids are low melting salts which dissolve cellulose directly in the melt.  Cellulose solutions in ionic liquids can be wet-spun (like viscose) whereas NMMO solutions have to be spun into an air-gap.  The main ionic liquids are based on 1-ethyl-3-methylimidazolium cations (EMIM) with either acetate or diethylphosphate anions.  They are thermally stable (melting below 100^oC), non-toxic, can dissolve up to 20% cellulose and can be recovered after use at efficiencies above 99%.  10% solutions of 592 DP cellulose in IL could be made in 1-2 hours at 85^oC and atmospheric pressure without the need for stabilisers against exothermic degradation.  NMMO requires 4-5 hours under vacuum at 120^oC with stabilizers to make a similar concentration.  Properties of the fibres wet-spun from the acetate IL were comparable to viscose, while those air-gap spun were like lyocell.  In both cases IL fibre extensibilities were about 2/3rds of the controls.  One slide showed sections of a highly microporous fibre wet-spun (i.e. viscose-like) from EMIMOAc, labelled “New generation of highly absorbent cellulose for hygiene and medical applications.”  It’s WI was said to be 140%, it could be made matt or bright, and had given good Syngyna results.  (From AiF Project No 16099N)

IL’s will also dissolve synthetic polymers opening the way to PET/Cell alloys.  A 50/50 alloy with aramid burned just like viscose!

In response to questions, Dr Ingildeev said factors affecting tenacity, fibrillation and brittleness (other than stretching) had yet to be checked.  Was a cellulose derivative formed prior to dissolution?  This remained to be seen, but no cellulose acetate or phosphate could be detected in the finished products.

Italian fibres from Germany (1)

Anemone Schmitsdorf of Kelheim Fibres (Germany) described the now familiar range of viscose rayon fibres based on inflation and alloying with cellulose derivatives: Bellini (ultraflat for papermaking), Bramante (segmented-hollow high-imbibition), Dante (segmented-hollow with derivative) and Verdi (viscose with derivative).  She concentrated on the self-extinguishing properties of Verdi and its 24.4 limiting oxygen index which make it suitable for flame redardant apparel for personal rather than industrial use.  It passes EN 14878 – Children’s Nightwear.

There were several questions:

·         Were the FR results affected by water hardness in washing?  This had not been detected.

·         Fibre strength? - less than viscose. 

·         Cost? – less than Nomex.

·         Blendability with other fibres? – work remains to be done.

Italian Fibres (2)

Ingo Berndt of Kelheim Fibres (Germany) provided more details on the properties of fabrics made from the Verdi, Dante, Bramante and Bellini viscose fibres, as evaluated by the Hohenstein Institute.

·         Verdi (derivative alloy fibre) gave a surprisingly high tear strength in an 80gsm spunlace:  almost double that of the control viscose despite having lower fibre strength.

·         Verdi needlefelts were however lower in tear strength than the control, and in these fabrics the Bellini (smooth flat cross-section) surprised with a significantly higher result.  Water imbibitions increased from 80% for the control fibre to 305% for Dante in the order, Bellini, Verdi, Bramante and Dante.

·         This translated into 80 gsm spunlaced fabrics with only Dante (+40%) and Bramante (+30%) showing higher absorbency (DIN 53923) than the control.

·         However in 210 gsm needlefelts the absorbencies were approximately 16 g/g for Dante, 18 g/g for Bramante and 19g/g for Bellini compared with a control at 14 g/g and Verdi at 13 g/g.  Here the alloys with highly absorbent cellulose derivatives (Verdi and Dante) absorbed surprisingly less than their non-alloy equivalents (the Control and Bramante respectively)

Italian Fibres (3)

Jan Beringer of the Hohenstein Institute (Germany) took over from Dr Berndt to review possible applications for these new fibres, highlighting clothing with thermal effects, wipes and reduced flammability clothing as the target areas.

One of the main functions of personal protective clothing is protection against cold, and fibres which absorb more moisture before feeling wet should be the best insulators.

·         Short term water vapour absorbency measurements (g/m²) on the spunlaced and felt samples showed Dante and Verdi to have advantages over the control viscose.

·         Thermal insulation measurement showed all fibres to be roughly equivalent, with Verdi felts having a slight advantage.

·         “Buffering capacity for liquid sweat F” (unexplained) was only better than satisfactory for the 50gsm Verdi and Bellini spunlace samples.

·         “Buffering capacity for liquid sweat G2” (unexplained) showed Verdi spunlace to be better than the control.

·         Thermal resistance of moist fabric measured as it dried out showed “Dante B” taking 85 minutes to dry versus about 20 mins for the control and 30 mins for Verdi.

The results appeared to be a selection from a much larger quantity of data and were not completely convincing.  However Dr Beringer concluded that Verdi has an advantage as a thermal insulator and Dante provides long lasting cooling effects.  Damp Dante appears to keep you cool for twice as long as damp viscose.

For Wipes a modified Martindale test compared the fabrics for removal of a range of contaminants (motor oil, make-up, tomato sauce and carpet dirt) in both wet and dry wiping against Kleenex, kitchen roll and Demakeup controls.  Bellini came out ahead for all but carpet dirt, giving subjective “greyscale” ratings of 4-5 against 3-4 for the controls.

Porous Fibre for Bone Regeneration

Nelson Cardosa of CENTI (Portugal) described his institute as the centre for nanotechnology, technical, functional and intelligent materials and in 2010 it employed 35 R&D staff on 40 industry projects.  On the bone-regeneration project they spin a 64 islands in a sea bicomponent with 89% of PBS sea and 11% of water soluble islands (e.g. Polyethylene oxide).  The hope is that when the islands are dissolved the porous fibres may allow better cell adhesion and vascularization.  Growth factors and antibiotics may also be added to the pores.  This principle has apparently been proved with fragrances. In response to a question, PBS was chosen in an earlier study of a range of biopolymers.

Technical Textiles in South America

Milton Bastos  a Consultant with MBB Enterprises (USA) focussed on Brazil as the powerhouse. It’s population of 190 million was 60% of the SA population and its GDP, which grew at 7.5% PA in 2010, was 70% of SA’s. It also consumes 80% of the regions technical textiles.

·         For the next decade GDP growth is expected to be 5%.

·         Brazil is a jeans and T-shirt market with cotton accounting for 60% of all fibres used. 

·         Fibre consumption will grow from 9 to 13 kg per capita with synthetics growing at 10%pa, the cotton share falling to 40%, all by 2020.

·         Technical textiles will grow at 15% per annum driven by performance sportwear (World Cup and Summer Olympics in 2014 and 2016) and the doubling of car production in the next 5 years.  New infrastructure projects will require more geotextiles.

·         Offshore oil discoveries will create a 40,000 tonne market for deep water polyester mooring ropes as 28 floating platforms for the production and storage of oil  from 2km deep wells are built by 2018.

·         After 20 years of stagnation, synthetic fibre production will be boosted by a new polyester plant being built by Petroquimica Suape (chips) and Unifit (industrial yarns for ropes, seatbelts and coating bases.)

Filters for Biomass Incinerators

Elke Schmalz of TITK (Germany) is evaluating high performance fibres for use in flue-gas filters on power stations using biomass.  Here, in addition to reducing particle emissions to meet the 20mg/m³ limit due to come into force in 2014, the filters must withstand potassium chloride and sulphate, hydrochloric acid, sulphurous acid and nitric acid in varying concentrations of oxygen from ambient down to 4%, and at temperatures in the 160^oC range with peaks at 190^oC. 

At present only acid resistant chromium nickel steel filters or PTFE filters work, most textiles being degraded too quickly.  Fibres and coatings are being evaluated by exposing them to 180^oC for up to two weeks and by hydrolysis at 130^oC in water vapour containing the various acids.  Nexylene® or Procon® polyphenylene sulphide (PPS) fibre is best for all but nitric acid, and if this is a key issue Tanlon® polysulphonamide fibre is required, but this is not so good in alkali.  PES (polyethylene sulphone), PI (poly imide), MF (melamine formaldehyde), and PAI (Polyamide imide) all failed against 2 or more challenges.

Piezoelectric fibres

Stephan Walter of RWTH Aachen (Germany) is making fibres from Polyvinylidene fluoride (PVDF), a thermoplastic semicrystalline fluoropolymer known for its ferroelectric and piezoelectric properties. The piezoelectricity depends on the presence of a crystalline, polar β-phase, and this could allow the development of a fibre sensor for measuring stress and strain.

The production of the sensor fibres is a four step process:

1.    The fibres are produced in the melt spinning process where the polymer chains are oriented, but here the predominantly the non-polar α-phase appears.

2.    Drawing of the fibre leads to transformation into the required β-phase.

3.    The fibre is polarized to rearrange the randomly oriented dipole moments and to create a macroscopic polarization. After the polarization process, deformation of the fibre leads to a measurable charge displacement.

4.    For the detection of the resulting voltage, the fibre must be contacted with electrodes in the last step.

The described steps have been undertaken in composite structures. One of the most promising applications of the piezoelectric fibres is the structural health monitoring of fibre reinforced composites. In this case,the vision is to measure the static or dynamic deformation of composite structures. With a special alignment of the fibres and the electrodes, the direction and the location of the deformation can be detected. 

RWTH is now working with bicomponent fibres where the core is a conductive polymer (electrode) and the sheath is PVDF.  Polyamide filled with carbon nanotubes is a possible conductive core.

New Air Filter

Sadahito Goto of Toyobo (Japan) described their Elitolon®R air filter as a unique polymer/additive combination, made into a bulky needlefelt and charged to a high charge density by an innovative method.  Graphs of pressure drop versus collection efficiency showed it to be capable of capturing 99.9% of 0.3 micron dust particles from a 10cm/sec air stream with a 20 pascal pressure drop where the best electreted competitor achieved 90% capture.  Charge retention was said to be “almost permanent” and when aged the filter could be recharged by washing and brushing, a procedure said to need some optimisation.  A halogen-free FR version has been developed which meets UL94  class HF1. Applications in cabin air filters, vacuum cleaners, photocopiers and air conditioners were illustrated. Questions aimed at discovering more about the polymer and charging system were left unanswered due to confidentiality.

Precise™ Nonwovens

Katou Kazufumi of Asahi Kasei Fibres Corp. (Japan) said Precise™ was a 3-layer SMS nonwoven made of 100% polyester with lower and more uniform pore size than other SMS products.  Heat sealability could be achieved by making either or both spunbond outer layers bicomponent with a low melting PET sheath. It could be used for high efficiency filters, dust-retentive tea-bags, coating bases (no strikethrough), surgical tapes (very breathable), OR drapes and gowns (breathable with high liquid barrier) and electrical papers for EMI shielding, electrolytic capacitor dielectrics, battery separators and flexible flat cable insulation.

High Loft Nonwovens

Mikito Yokoyama of Teijin Fibres Ltd (Japan) described their Elk® as a high loft nonwoven made from a bicomponent fibre with a polyester core and an elastomeric polyester sheath, the core being off-centre and the resulting crimp being spiral.  It is intended to replace polyurethane foam in upholstery construction on the basis of:

·         Improved breathability.

·         60% lighter than PU foam of similar performance

·         Reduced density (down 30%) even under load.

·         Ability to pass Japanese FR tests.

·         Low and non-toxic smoke when in a fire.

·         Recyclable into fibres or plastics or energy.

Current applications are in train seats mattress covers and padded bras.  Asked if it could be used in sports clothing and shoe insoles Dr Yokoyama thought not: it’s durability may be too low for apparel use.

Rayon Tyre-Yarn

David Wunderlich of Cordenka (Germany) said they made 120,000 tonnes per year of industrial yarns at the Obenburg factory, 32,000 tonnes of which were cellulosic.  They had worked on NMMO and phosphoric acid routes to industrial yarns while part of Acordis, but had discovered that the in-rubber fatigue resistance of the solvent-spun celluloses was significantly inferior to that of viscose yarns.  They were now collaborating with TITK on IL solvents for cellulosic tyre yarns and developing PP/Cellulose and PLA/cellulose composites containing about 30% of the viscose tyre yarn.

New Fibre Tests

Ulrich Mörschel of Textechno (Germany) described their Favimat+Autofeed system which can take single filaments from  a flock and feed them to a universal single-fibre tester which can now measure fibre metal friction and bending stiffness as well as tensiles.  Tensiles of short-cut fibre (3-8mm) can also be measured.  They hope to ship the first systems next year and will retrofit the autofeed to existing Favimat+ testers.  They also supply a fabric drape tester which uses the burst-test principle to deform the fabric, a capacitative yarn eveness tester and the Vibrascope fibre dtex measurement.  (Textechno took over Lenzing Instruments.)

Antimicrobial Tencel for Workwear

Edith Classen of the Hohenstein Institute (Germany) has evaluated antimicrobial lyocell fibres spun by TITK and converted into knitted and woven fabrics by STFI.  The fibres were:

·         Lyocell plus Zinc Oxide

·         Lyocell ion exchange fibre plus ZnO

·         Lyocell ion exchange fibre plus Silver Nitrate and TiO₂

The ion exchanger was a sodium polyacrylate powder with a 10 micron particle size.  The yarns and fabrics were blends of 10% of the active fibres with 50% PET and 40% of the fibrillation-resistant Tencel® A100.

There were no problems producing the fibres or fabrics.  Tenuous conclusions were drawn related to Hohenstein skin model fabric comfort, antimicrobial properties and the whiteness of the fabrics containing silver, all of which were described as good

Tencel Nanocomposites

Marcus Krieg of TITK (Germany) makes what he calls a cellulosic nanocomposite by adding TiO₂ particles to lyocell dope and spinning it.  The TiO₂ dispersion was made in water and aqueous NMMO, with and without sodium polyacrylate thickener, use of this giving the best stabilisation of the dispersion.  Fabrics made from the fibre could claim UV protection.  They had also tried adding Permethrin insecticide to lyocell dope and had spun it into fibre to make an insect repellent cellulosic nanocomposite.  Washing tests show the spun-dyed approach is more durable than surface treatment.

Tencel/Chitosan

Johanna Brandner of the University Hospital, Hamburg (Germany) described the testing of this antimicrobial and haemostatic fibre as a wound dressing for infected wounds.  Fibres with 1 to 5% chitosan (>90% deacetylated chitin) were compared with <1% chitosan and a Tencel control on pigs ear tissue. Skin samples comprising epidermis and dermis with a diameter of 8 mm are derived from live pig ears and are placed dermis down on gauze in cell culture wells. They are supplied with medium in such a way that the dermis is in contact with the medium while the epidermis is in contact with the air. The skin surface is infected with a defined concentration of P. aeruginosa and subsequently incubated for a specific period of time. Then fabrics made of TENCEL®, TENCEL® C (low chitin) and TENCEL® C (high chitin) are placed onto the infected skin and incubated for another period of time.  Finally the fabrics are removed and fabrics as well as the infection models are pressed onto agar plates which are subsequently incubated over night at 37°C. Growth of P. aeruginosa on the agar plates is evaluated. The results showed a clear benefit for the low level of chitin but suggested that the high level was inhibiting the healing of non-infected wounds.

Asked if both wet and dry wounds had been studied, Dr Brandner said only dry wounds so far.  One questioner pointed out that chitosan was animal-based and therefore disallowed by the EU for use in wound dressings.  Despite the “>90% deacetylation” statement in the presentation, in questions the level was given as “80-90%”. Chitosan molecular weight was also important, and more work was needed on its concentration in Tencel.  Asked if bacteria could develop resistance to chitosan, Dr Brandner thought it to be better than other antimicrobials but “more work was needed”.

Carbon Fibre from Tencel

Gisela Goldhalm of Lenzing (Austria) promoted the well known physical differences between viscose and Tencel as the logic for using Tencel as a carbon fibre and activated carbon fibre precursor.

Hi-Vis Tencel

Ksenija Varga of Lenzing (Austria) has developed a spun-dyed yellow Tencel for high visibility clothing.  It is more comfortable to wear for the sports market and is now being developed in a flame retardant version for the professional workwear market.  Surprisingly, it was not described as a cellulosic nanocomposite.

 

Calvin Woodings

22/9/2011