new series This section
new series This section highlights recent IP (patent) activity that is relevant to the field of bioplastics. The information offered is intended to acquaint the reader with a sampling of know-how being developed to enable growth of the bioplastics and bio-additives markets. U.S. Patent 10,647,093 (May 12, 2020), “Biodegradable Sheet”, Daphna Nissenbaum, Tal Neumann, Dori Pelled, Shai Garty and Nili Konieczny; Tipa Corporation (Hod Hasharon, Israel) This patent teaches a biodegradable multilayer sheet where one layer is a direct contact layer for liquids allowing the film construct to have lower water vapor transmission rate, lower oxygen transmission rate and improved heat seal processing and integrity. Typical to this invention are three or five layer film constructs. The layer in direct contact with the liquid(s) is selected from polycaprolactone (PCL), polyhydroxybutyrate (PHB), polydioxanone (PDO), polyglycolic acid (PGA), polybutylene succinate (PBS), poly(butylene succinate adipate) (PBSA), polylactic acid (PLA), polybutylene adipate terephthalate (PBAT) as well as polyhydroxyalkanoate copolymers. The individual layers can be a mixture of the biodegradable polymers The multilayer film constructs can also include polyvinyl alcohol as a center layer with defined tie layers to the bio based exterior film layers. As previously stated the invention teaches achieving improved barrier properties and heat seal performance but also emphasizes the use of biodegradable polymer and copolymer layers for effective biodegradation rates for after use disposal, e.g. compostability. The observed performance enhancements of the film constructs exceed the additive effects of the individual polymers. U.S. Patent 10,669,598 (June 2, 2020), “Catalytic Biomass Deconstruction”, Ming Qiao, Randy D. Cortwright, Dick A. Nagaki and Elizabeth Woods, Virent Inc (Madison, Wisconsin) This patent teaches a hydro-deoxygenation process for reducing biomass, specifically lignin and cellulose to renewable oxygenated chemicals which can be isolated or further used in bioreforming processes to produce renewable aromatic and aliphatic chemicals. This catalysed process focuses on non-edible, second generation feedstocks such as agricultural residue, wood materials, energy crops and municipal solid waste. The process is typically run at 240 – 300 C, 1000 – 1450 psi using hydrogen and a supported catalyst, which can be a mono or multi metal composition. Typical products of the hydro-deoxygenaton are alcohols, ketones, cyclic ethers, polyols and carboxylic acids. Key teachings are the use on nonfood based feedstocks which may offer lower cost and higher availability than traditional feedstocks such as sucrose. By: Barry Dean, Naperville, Illinois, USA BIOPLASTIC patents U.S. Patent 10,633,522 (April 28, 2020), “Renewable Resin Composition and Product Prepared From The Same”, Ha Thuc and Nhan Chi; Green Whale Global Co, Ltd (Seoul Korea) In an effort to address the environmental plastic residue pollution in balance with offering price/performance competitiveness in a biodegradable formulation this patent teaches a composition that is 100 parts by weight cassava starch, 100 to 200 parts by weight of polybutylene succinate (PBS), 20 to 120 parts by weight of polybutylene adipate-co-terephthalate (PBAT) and 10 to 40 parts by weight of a plasticizer, e.g. glycerine oil. The intended product applications as taught can be a film, straw, container or tray. The bio-content as determined by ASTM-D6866 can range from 35 to 70 % by weight. The use of PBS and PBAT offset the base disadvantages of cassava starch; high water solubility and weak mechanical properties. If required a further teaching is the use of an impact reinforcing agent such as core shell methacrylate-butadienestyrene (MBS) or other like impact modifiers. This type of composition can be used to make films, containers, straws and other formed articles. U.S. Patent 10,655,008 (May 19, 2020), “Biodegradable Polymer Composition For The Manufacture Of Articles Having A High Heat Deflection Temperature”, Nicola Marini and Angelos Rallis, Novamont S.P.A. (Novara, Italy) Reference: WO 2013/124301 A biodegradable composition based on polylactic acid is taught offering high heat deflection temperature and good dimensional stability for injection molded and thermoformed articles. The composition taught is 50 – 95 % by weight polylactic acid, 5 – 50 % by weight of an aromatic aliphatic polyester that is at least in part renewable and/or biodegradable; 1- 25 % by weight cellulose fiber (with respect to the total weight of the biodegradable polymer composition), and 1- 10 % by weight of a nucleant (with respect to the total weight of the biodegradable polymer composition). The composition may also contain very low levels of an anti-caking agent, inorganic filler and hydrolysis stabilizer. The nucleating agents taught are polyesters based on repeating units of 1,4-butylene succinate and/ or in combination with talc. The combination of improved heat distortion temperature (HDT) and dimensional stability of the molded article is tailored by the make-up of the polylactic acid composition. 50 bioplastics MAGAZINE [04/20] Vol. 15
Patents U.S. Patent 10,669,417 (June 2, 2020),”Recyclate Blends”, Yelena Kann and David Boudreau, CJ Cheiljedang Corporation (Seoul, South Korea) Reference: WO2014/040278 This patent teaches the addition of PHA type polymers to recycled PVC and the benefits to physical properties and processability. As polyvinylchloride (PVC) undergoes a heat history degradation of mechanical properties can occur. The addition of poly (3-hydroxybutyrate-co-4-hydroxybutyrate) copolymer with levels of 4-HB of 8.5 – 45 % and total copolymer loadings of 10 – 50 % can result in improved properties for the recycle PVC composition. Tensile and tear strength properties improve for recycled PVC with 15 – 20 % of PHA copolymer; further tailoring of the copolymer composition with regard to 4-HB comonomer content is shown to further enhance tensile properties by 15 – 30 % versus control recycled PVC. U.S. Patent 10,669,357 (June 2, 2020), “Polyvinylbutral-g- Polylactide Copolymer”, Yannan Duan and Roger W. Avakian, Polyone Corporation (Avon Lake, Ohio USA) Reference: WO2017/035070 Copolymers of a polyvinyl butyral (PVB) backbone and polylactic acid grafts are taught. These graft copolymers are amorphous and can be used to produce clear and flexible films which maintain clarity and ductility up to use temperatures of 80 C. The copolymer is an in-situ reaction product of polyvinyl butyral with lactide monomer to form the side chain graft polymers of PLA. The PVB-g-PLA copolymers offer renewable content based materials and end of life article compostability. The criticality of the in-situ formation of the PLA graft to obtaining clarity, flexibility and ductility is illustrated by control comparisons with physical blends and transesterification catalysis of the PVB and PLA polymers. U.S. Patent 10,556,857 (February 11, 2020). “Hydrazide Compounds Suitable For Nucleating Polylactic Acid Polymer”, Nathan E. Schultz, Liming Song and B. Fuming, 3M Innovative Properties Company (St. Paul, Minnesota USA) Reference: WO2016/209663 Rapid and controlled crystallization of polylactic acid is key in developing and locking in properties during commercial processing of PLA in the form of fiber, film and other molded articles. Compounds that nucleate crystalline formation from the PLA melt are key. This patent teaches the use of hydrazide compounds to effect the crystallization. The chemical structure of the hydrazide can be modified to effect and tailor changes in the crystallization behavior of the PLA polymer. The concentration of the hydrazide nucleating agent can range from 0.01 to as high as 5 weight %, though preferred ranges tend to be 0.1 – 1.0 weight per cent. The patent illustrates the effect of 1 weight % hydrazide on the effect of the crystallization temperature when incorporated versus a control; PLA with no nucleating agent yields a crystallization peak temperature of 102.2 at a cooling rate of 5 C/minute vs a PLA with 1.0 % hydrazide nucleant with a crystallization peak temperature of 121.3 at a cooling 5 C/minute. U.S. Patent 10,626,420 (April 21,2020), “Composition and Methods For Producing Isoprene”, Marguerite A. Cervin, Gopal K. Chotani, Frank J. Feher, Richard La Duca, Joseph C. McAuliffe, Andrei Miasnikov, Caroline M. Peres, Aaron S. Puhala, Karl J. Sanford, Fernando Valle, Gregory M. Whited; Danisco U.S INC (Palo Alto, Ca USA) and The Goodyear Tire and Rubber Company (Akron, Ohio USA) This patent teaches a method of producing a bio-based cis-polyisoprene, via culturing recombinant cells under suitable culture conditions for the production of isoprene. The cells comprise nucleic acids encoding a heterologous isoprene synthase polypeptide; and two or more heterologous mevalonate (MVA) pathway polypeptides. The cells are shown to produce greater than 400 nmole/gwcm/hr of isoprene, which is more than 0.002 molar percent of the carbon that the cells consume from a cell culture medium into isoprene. The average volumetric productivity of isoprene is greater than 0.1 mg/Lbroth/hr of isoprene. The teachings show isoprene production is at least 0.0037 grams of isoprene per gram of dry cell mass (gdcm). The pathways to isoprene are taught in fungal, bacterial, plant and algal cells. Cis-polyisoprene, i.e. isoprene rubber is used for footwear, sporting goods, mechanical apparatus boot coverings but mostly for tires. The concentration of the hydrazide nucleating agent can range from 0.01 to as high as 5 weight %, though preferred ranges tend to be 0.1 – 1.0 weight per cent. The patent illustrates the effect of 1 weight % hydrazide on the effect of the crystallization temperature when incorporated versus a control; PLA with no nucleating agent yields a crystallization peak temperature of 102.2 at a cooling rate of 5 C/minute vs a PLA with 1.0 % hydrazide nucleant with a crystallization peak temperature of 121.3 at a cooling 5°C/minute. bioplastics MAGAZINE [04/20] Vol. 15 51
