Friday, 24 October 2014

Biodegradable Gas Barrier Films

Domenico de Angelis of Nippon Gohsei (Japan) believes their Nichigo G-Polymer™ (PVOH) makes a better gas barrier film than EVOH and in dry atmospheres it can be 50x better.  So for dry foods in controlled storage at humidities below 60% RH PVOH will outperform EVOH to an extent that downgaging  and cost saving is possible.  

PVOH gives films with glass-like transparency which biodegrade like cellulose and are therefore fully compostable.  The packaging film used PVOH as the middle layer of a sandwich with PLA as the outer layers.  There were problems with adhesion and these had been solved using a special tie resin.  The 3-layer film could also be ground and recycled as PLA; the PVOH being water soluble could be washed away. A typical construction would be 20 microns of G-Polymer inside  30micron layers of PLA each bonded to the G-Polymer with 10microns of adhesive to give an oxygen transmission rate of 0.02 ccs/square metre/day at 23C and 50%RH.

Nippon Gohsei make 70,000 tonnes/year of PVOH in Japan.  Nichigo G-Polymer™ is the world’s first amorphous PVOH and combines the strengths of regular PVOH and EVOH.

Friday, 26 September 2014

Certification of Biopolymers

More from AIMPLAS Valencia...
Miriam Lübbecke of DIN Certco (Germany) specialises in biopolymer certification using a scheme which is totally transparent with all details publically available on their website.  When a manufacturer applies for a certificate, DIN Certco assesses the relevant literature and decides how to test the product.  It uses appropriate independent test laboratories chosen from its list of 130 accredited and contracted testing partners, issues a report on the results,  and if appropriate, the certificate of conformance and permission to use the logo.  “Biobased” certificates cover three levels, 20-50%, 50-85% and >85% biobased according to ASTM D 6866 methods which requires a total organic carbon of >50% and a C14 content above 20%.  Testing is required every second year.

“Compostable” certificates can include 4 logos, “the seedling” for industrial compostability, and 3 “DIN-Gepruft” logos covering industrial, home composting and additive content. ASTM D6400 is among the approved tests, but only the Australian standard AS 5810 is used for home composting certification.  The tests include ultimate biodegradability, disintegration, plant toxicity, EN 13432 chemical analysis and, for home composting the ASTM E 1676 earthworm toxicity test.

“Recycled Content” is determined by DIN EN ISO 14021 and audits of the manufacturing site to determine traceability under DIN EN 15343.  A new “All-in-one” DIN Certco logo covering all 4 properties is now available.

Sunday, 21 September 2014

Biocomposites from Starch, Natural Fibres and Polymers

More from AIMPLAS, Valencia...
Leon Mentik of Roquette (France) explained how they bought maize, potatoes, wheat, tapioca and peas for processing and used the extracted starches to make bioplastics.  After cellulose, starch was the second most abundant polymer on the planet with 1.3 billion tonnes being produced annually in plants.  6% of this (80 million tonnes/year) is extracted very easily, the by-products being proteins and fibre for use as food.  Starch is highly reactive and easily grafted or alloyed with other materials to add desirable functionalities.  It can be used directly to make starch-based plastics, either as blends with other polymers or in the form of durable thermoplastic starch.  It can also be easily hydrolysed to glucose to provide the starting point for the whole range of bio-based or bacterially produced polymers.

Gaialene® is Roquette’s durable, i.e non-compostable, starch-based plastic which has been certified against ISO 14040/44 by Price Waterhouse Coopers with a carbon footprint of 0.74 kg CO2 eq./kg resin or ~1/3rd that of PP.  It has applications in replacing polyolefins in  films, injection moulding and foams, to produce  shopping bags (for recycling or incineration), multilayer shrink wrap, moulded paint containers, fabric coatings, mud-guards, sound insulation and packaging foams.  It is fully recyclable, GMO-free and does not compete with food crops.

Sergio Fita of Aimplas provided another comprehensive overview of the Technological Institute and its work on composites for those who joined the conference late.  He reiterated the variability issue which arises because natural fibres are inherently variable and moisture sensitive and said AIMPLAS was working to overcome this deficiency.  Examples of successes were the woven Flax/Jute battery case which used an epoxidised acrylate soybean-oil resin (ASEO); the Roadside Grit Box using wet compression moulded Flax/biobased unsaturated PET resin (thermoset); the woven flax/PLA tractor door, the Cayley project honeycombs based on FR-treated bio-resins and natural fibres and the Ecoplast project for automotive parts made by extruding PHB polymer onto flax fabrics, calendaring to impregnate and then moulding to shape.

Wednesday, 3 September 2014

Biopolymer Waste in Spain

More from AIMPLAS Valencia...
Francesc Giró of the Catalonia Waste Agency was concerned that the desertification now occurring in southern Europe needed to be corrected by adding massive amounts of organic matter to the soil, and this required more composting infrastructure.  In reality 70% of waste organic matter in the region is still land-filled or incinerated and action was needed to allow this to be collected separately and composted.  The target is to compost 50% of organic matter by 2020 and in Catalonia a tax on landfill and incineration is encouraging movement in this direction.

  • ·         Door to door collection of food waste is required.
  • ·         Compostable bags need to be used for this collection.
  • ·         Disposable nappies were a huge problem, accounting for 2.5% of all waste.
  • ·         Compostable diapers could make a large contribution to compost production, but they were currently twice the price of the petro-diapers.
Judit Janasa of TOMRA Sorting and Recycling commented on the difficulties of separating mixtures of plastics containing biopolymers but concluded that their sorting machines would soon be able to remove compostable bioplastics from the recycling stream.  They have installed 3470 sorting machines worldwide, mostly in the Iberian peninsula.  These machines use electromagnets, high intensity visible light, infra-red both transmitted and reflected, X-ray, atomic density, and laser fluorescence sensors to identify different materials.

The machines are tuned to the key wavelengths reflected or transmitted by each polymer and digital images taken at these wavelegths are analysed pixel-by-pixel so that for a bottle for example, the cap, label and body polymers are identified and recorded.  Problems arise with black polymers (no reflection), and labels made of paper prevent the underlying polymer being seen.  PLA and PET bottles which look identical can be separated easily.  The software in use can be updated for every new polymer once samples have been tested.

Asked how multilayer bottles or films would be treated, Ms Janasa said the majority polymer would take precedence.

Tuesday, 12 August 2014

Biopolymers from waste and Compostable Packaging

More from AIMPLAS 2014 - Valencia..

Mercedes Villa-Carvajal, a biotechnology researcher at the Ainia Technology Centre (Spain) described the use of waste liquor from the orange juice processing industry to produce poly-hydroxybutyrate for bottle production.  The PHB was compounded with cellulose fibres and fillers and injection moulded to make the bottles. (“Phbottle”)

Pretreatments prepared the raw material to receive an inoculation of microorganisms.  Bioprocessing involved fermentation and separation of the required monomer.  Post treatment involved polymerisation.

In principle, any carbon source (e.g. food waste) could be pretreated to receive any one of a range of microorganisms, patented or unpatented, GMO or not, provided with oxygen, and fermentation would result.

Jordi Simon and Matthias Klausmann of BASF (Germany) used the term BioCom to refer to their compostable polymer recommended for use where organic matter is left behind after the food has been taken out of the packaging.  BioCom in fact appeared to be being used as a term of the biodegradable and compostable properties of their Ecoflex® polymers which could be made either from petro- or bio-based sources as required. Ecovio® is their blend of Ecoflex® and PLA.

Ecovio® is finding applications as an agricultural mulch film and as a bag for food waste intended for composting.  A new application was demonstrated at the conference, a 100% biodegradable coffee capsule designed to allow coffee and its carrier to be added to the compostable waste stream.  The capsules packaging was also a 3 layer compostable film.  The system had yet to be adopted by any of the major coffee capsule makers and appeared to be a unique design using a permeable tea-bag nonwoven top cover rather than air-tight foil.

Wednesday, 30 July 2014

Customised Bioplastics

More from AIMPLAS 2014 - Valencia...

Chelo Escrig of AIMPLAS ran through a range of bioplastics developments underway at AIMPLAS. A new extrudable polyvinyl alcohol had been developed and this allowed production of a 3-layer oxygen and moisture barrier film comprising polyvinyl alcohol sandwiched between layers of PLA (“C-Calpe” and “Bio4map”).  It could also be co- injection moulded with polyethylene. PVOH was unique among polymers in that it was not polymerised in that form.  Vinyl acetate was polymerised to PVAc and then hydrolysed back to PVOH.
PLApack was a highly plasticised version of PLA film which had low modulus and hence suitable for a wider range of packaging films.
Hydrus was a PLA tubing suitable for micro-irrigation with an operating temperature range up to 103oC.
Biopolyim A was a soft PLA containing newly developed plascticisers based on lactic acid oligomers.
Innorex was PLA produced without metal catalysts using ring-opening polymerisation of a lactide in a reactive extrusion process.  The lactide was fed into an extruder with laser, microwave and ultrasound being shown as the initiators of the polymerisation.
BioBottle was injection moulded from PLA with supercritical CO2 injected into the first of two extruders.  The resulting volatiles were vented from the second extruder which delivered odour-free PLA to the mould.

David Bertomeu of FKUR reviewed their range of compounds for use in food packaging.  They buy PLA, PHA, PBAT, PBS and Cellulose Acetate and compound them in different ways to make Bioflex®, Biograde®, and Fibrolon®  for use in agricultural mulch films and flower-pots. For the catering industry they make a complete range of compostable plastic cups, plates, cutlery and disposal bags to that the entire table setting and any food waste can be gathered for delivery to the composter.  They also buy biobased PE and make Terralene™ blends to get a range of properties which allow substitution of the full range of polyethylenes from LDPE to HDPE.

Saturday, 12 July 2014

Bio-based Polyamides

More from AIMPLAS 2014 - Valencia...

Pep Catalan, Sales Manager – Speciality Polyamides for Arkema (France) said they intended to continue to lead the field in production of high performance polyamides based on castor oil chemistry.  Their Rilsan® process, established in the 1950’s as a way of avoiding the Dupont nylon patents, did not compete with food, avoided deforestation and used a crop which could be grown in semi-arid areas.  It was now a high-performance, high temperature resistance bio-plastic for engineering applications.

Compared with the petro-polyamides, on a cradle to factory gate basis, it reduced global warming potential by up to 52%, saving 4.7 tonnes CO2 emissions for every tonne of polymer produced.

A new elastomeric version, a PA/polyether block copolymer called “Pebax”, is now available.  Here the PA is bio-based but the polyether isn’t.  “Pebax Rnew” is however based on 95% renewable carbon and has high energy absorbtion and recovery.  This springy polymer is being developed for running shoes and ski-boots.

“Rilsan Clear” is a cycloaliphatic PA, now also bio-based. It has glass-like transparency.

Wednesday, 2 July 2014

A New Engineering Bio-Composite

More from AIMPLAS 2014 - Valencia...

Frank Steinbrecher of Mitsubishi Chemicals (Germany) introduced Durabio®, a renewable durable polycarbonate-like bio-polymer based on isosorbide made from sorbitol which in turn came from glucose made from starch.  

The technology had been developed by Roquette.  In 2010 the Durabio® capacity was 300 tpa and last year it was 5000 tpa.  The injection moulding grade has high hardness and the end-products are positioned between PMMA and PC for transparency. Compared with PC, Durabio® also performs better on weathering but is slightly worse for tensile strength.  It is being used to make high-gloss coatings for mobile phones by injection moulding and as glass-replacements in roadside sound barriers by extrusion.  Automotive parts are also made by extrusion and have proved to have the necessary optical, chemical and safety characteristics for interior trim.  It is less flammable than either PMMA or PC.  Asked if it was weldable to ABS like PC is, Mr Steinbecher thought it was, in principle, but Mitsubishi would be happy to test this.
Mitsubishi’s GS Pla was their biodegradable polymer originally made from petrochemicals and now available from bio-succinic acid.  Despite its name it is a polybutyl succinate and not a PLA.

Thursday, 26 June 2014

Biopolymers in Nestlé

More from AIMPLAS 2014 - Valencia...

Carlos de la Cruz, the Head of Regulatory Affairs for Nespresso Capsules criticised the industry for confusing consumers with too many eco-claims and argued that the packaging was the key to improvement.  It not only protected the product and kept it fresh but could also be used to communicate with and educate the consumer.  Communications had to be based on comprehensive life-cycle assessments of the food and its pack from farm to fork.  Bioplastics made from foodcrops can improve the environment but crops do need fertilisers and pesticides.  These are based on fossil carbon and have additional adverse impacts on the ecology per se.  Irrigation if needed is a further negative impact in LCA terms.  Furthermore, bioplastics food packs must protect the food from spoilage to the same extent as petro-polymers or the resulting extra wastage will easily nullify any benefits. 

Examples of successful packaging using biopolymers where the benefits were explained on the packs included Purina One Beyond dog food, PLA twist wrap for sweets on Quality Street in the UK, Herta Sweet Ham using a 20% bio-sourced wrap in France, the Davy Milk carton bioplastic cap and “Vittel” water bottles using 30% biosourced PET in France.  

The Bioplastic Feedstock Alliance had been formed this year and brought together companies such as Nestlé, P&G, Unilever, Coca Cola, Heinz, Nike and Ford among others.  The next generation of bioplastics (Gen 3) would be derived from non-food sources such as wood, waste, drought resistant plants and algae.  (Gen 1 was PLA, described as food-based and unsuitable for widespread use in packaging.  Gen 2 were the “drop-in” polymers suitable for widespread use but expensive and made from sugar via ethanol.)

Monday, 23 June 2014

Green and Sustainable Composites

More from AIMPLAS 2014 - Valencia...

Kerry Kirwan of Warwick University (UK) has re-evaluated the use of jute, flax and hemp in composite reinforcement.  These materials have been used mainly in electric cars where weight reduction c.f steel or GRP is a virtuous circle, and where, unlike the money-no-object F1 cars, carbon fibre is too expensive.  Unfortunately the variability of tensile properties from these natural product prevents them from performing as well as might be expected, so Warwick has been looking at their energy absorbtion properties with applications in crash-structures in mind.

Surprisingly, woven hemp or flax crash cones in a biobased resin matrix worked better than aerospace grade carbon fibre in epoxy resin.  These biocomposites  have now been incorporated into a Lola F3 car.

Marta Pascual of DSM Composite Resins (Holland) listed the challenges facing the EU composites industry:

  • ·         Replacement of styrene due to its problems of flammability, toxicity and odour.
  • ·         Replacement of the catalysts used for hardening: cobalt salts and tertiary aromatic amines.
  • ·         Reducing dependence on fossil carbon sources and their price volatility.
One of their key products was in fact that contradiction in terms, the thermostable thermoplastic, an unsaturated polyester resin used in automotive applications (“Palapreg”) and artificial marble (“Synolite”).

Beyone™ (201-A-01) was a  40% renewable, cobalt-free, styrene-free resin used in the manufacture of wind-turbine blades by DSM/Siemens.  Coupled with Blucure™ curing technology, it had won the JEC Innovation award (2012).