Polylactides PLA

In cooperation with the Neste company, the Technical Research Centre of Finland (VTT) [37] prepared a comparative LCA for two diaper systems one of which is based on polyolefins (PP, PE) while the other uses PLA (made from maize, wheat and sugar beet). For most of the parameters studied, the polyolefin-based diaper shows better results than its biodegradable 

Determined by deducting CO2 absorption from totals (Net fossil CO2) Refers to feedstock carbon only. Data for Year 5 and long-term assumed to be identical with Year 1 Data for PLA from CARGILL DOW [34] and personal communication with E. Vink [35] Data for petrochemical polymers from APME [16, 36]  

Based on the information that is currently available one can expect the environmental performance of PLA according to current production methods to be less advantageous than most starch polymers but clearly more beneficial than for PHA. Substantial improvements are expected for PLA for the future. 

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Polylactide (PLA)-CaS04 composites toughened with low molecular weight and polymeric ester-like plasticizers and related performances. European Polymer Journal 44 3842-3852. 

The neutral fats used in the preparation of the hydrophobic core of the several liposphere-vaccine formulations described here included tricaprin and tristearin, stearic acid, and ethyl stearate. The phospholipids used to form the surrounding layer of lipospheres were egg phosphatidylcholine and dimyristoyl phosphatidylg-lycerol. Polymeric biodegradable lipospheres were prepared from low molecular weight polylactide (PLA) and polycaprolactone-diol (PCL). 

Polylactide hydrogel, 13 741 Polylactides (PLAs), 20 297-318. See also Poly(L,L-LA) entries breakthroughs in synthesis of,... 

Carboxylic Acids Obtained by Fermentation of Carbohydrates Lactic (2-hydroxy-propionic) acid obtained by fermentation of glucose and polysaccharides is used by NatureWorks (Cargill/Dow LLC) to prepare polylactide (PLA), a biodegradable or recyclable polymer with a potential production of 140000 t a-1 (Scheme 3.4) [23], This and other potential useful reactions from lactic acid have been reviewed by Datta and Henry [24],... 

Much has been written about Cargill Dow LLC s polylactide (PLA) polymer, also known as NatureWorks PLA. PLA is a thermoplastic produced from biomass sugars by fermentation. The fermentation product, lactic acid, is converted into a lactide that is purified and polymerized using a special ring-opening process (18). 

FIGURE 6.2 (See color insert following page 530.) Intumescent polylactide (PLA) during a cone calorimeter experiment. Note the small flames on the side of the intumescent cake showing how the intumescent coating smothers the fire. 

Polylactide (PLA) is the leading polymer type among biodegradables with global production capacity for this material amounting to about 250,000 tonnes per annum in 2005. Starch-based polymer capacity is approaching 60,000 tonnes per annum. 

The above mentioned scaffolds were made completely of the ceramic materials. Other potential materials which could be used to fabricate a novel construct for the repair of ciitical-sized bone defects is a novel material made of biodegradable polymer reinforced with ceramics particles. The properties of such a composite depend on 1) properties of the polymer used for the matrix and properties of the ceramics used for the reinforcement, 2) composition of the composite (i.e. content of ceramic particles) and 3) size, shape and arrangement of the particles in the matrix. Several polymer-composite composites have been used for scaffolds fabrication including polylactide (PLA) and polycaprolacton (PCL) reinforced with calcium phosphate (CaP) micro and nanoparticles. Authors proposed a novel composite material by blending copolymer -Poly(L-lactide-co-D,E-lactide) (PLDLLA) a copolymer with a ceramic - Tri-Calcium Phosphate... 

The second concept for the generation of monolithic polymers is based on diblock copolymers which were prepared by Hillmyer and coworkers [27]. These copolymers contain oriented nanoscopic cylinders of the degradable polymer polylactide (PLA) which were embedded in polystyrene. The latter served as an inert thermoplastic matrix, while PLA could be selectively removed under well-defined conditions using sodium hydroxide in aqueous methanol. The resulting mesoporous monolithic polystyrene contains nanochannels with defined pore size. The major drawback of this material free of any cross-linker is associated with reduced mechanical and chemical stability. 

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