Industrial poly lactide

Polyesters, specifically polylactides and poly(lactide-co-glycolide)s have played a critical role in the development of polymer-based CR technologies. The biocompatibility and the well-established safety profiles of PLA and PLGA polymers have made them the polymer of choice for CR applications. However the off-patent status of these polymers makes them freely available for research in industry as well as academia. This has led to a vast number of patents covering various applications of these polymers within the drug delivery sector. Due to these issues, very limited scope remains to utilize these polymers to reformulate generic, off-patent drugs. 

Martins, I. M., Rodrigues, S. N., Barreiro, M. F., and Rodrigues, A. E. (2011). Release of thyme oil from poly-lactide microcapsules. Industrial and Engineering Chemistry Research, 50, 13752-13761. 

Most types of Hot melt adhesives used in the mannfacture of laminates and in rapid Packaging industry applications are mineral oil-derived, hydrophobic and essentially non-dispersible, so they cannot be considered as renewable. However, some basic polymers have been prepared over the last decade from vegetable sources, which are renewable, and are adhesive, although these properties have limitations. These include poly(hydro-xybutyrate/hydroxyvalerate) (PHBV), poly(lactide) (which has poor thermal stability), and starch esters. Adhesives based on sulphonated polyesters with polar petroleum waxes have improved adhesion and adequate water dispersibility. In general, however, the perfect adhesive from renewable resources with satisfactory adhesion properties remains to be discovered. 

Rhim, J.W., Mohanty, K.A., Singh, S. P. and Ng, P.K.W. (2006). Preparation and properties of biodegradable multilayer films based on soy protein isolate and poly(lactide). Industrial and Engineering Chemistry Research, 45,3059-3066. 

Poly(lactide) (PLA) is a thermoplastic, biocompatible and capable of biological and hydrolitical degradation polymer. A few years ago, production of PLA was very expensive and only recently, after the costs of its production came down, it has become widely applicable in many aspects of everyday life. As a result, PLA is the most technically advanced, biodegradable polymer. On an industrial scale, it is produced from lactic acid that is obtained in process of glucose fermentation [48]. 

Apart from these traditional methods, research directed toward the syntheses of biodegradable polymers has emerged as an important area. For polyolefins, metal complexes that initiate and catalyze oxidations are sometime added in the final polymer (see Section 8.3.1). Such additives hasten the biodegradation of polymers to some extent. In so far as polyesters are concerned, lactic acid can be produced on an industrial scale by the microbial fermentation of agricultural by-products. Therefore for medical and some other applications poly-lactide (PLA) as a material is preferred over nonbiodegradable polymers (see Section 8.4). 

Auras, R., Harte, B., Selke, S. Sorption of ethyl acetate and d-limonene in poly(lactide) polymers. Society of Chemical Industry. J Sci Food Agric 0022-5142(2005). 

Leuprolide acetate/poly(DL-lactide-co-glycolide) Lupron Depot , Takeda Chemical Industries Endometriosis... 

Nishida, H., Fan, Y, Mori, T. et al. (2005) Feedstock recycling of flame-resisting poly(lactic acid)/aluminum hydroxide composite to L,L-lactide. Industrial and Engineering Chemistry Research, 44, 1433-143. 

PUs have been developed and thoroughly investigated for various industrial and biomedical applications [1-3], By alternately connecting soft and hard segments together through urethane bonds, assorted PUs, such as poly(E-caprolactone) (PCL) containing block PUs [21], polylactide (PLA)-based PUs [22], and poly(E-caprolactone-co-lactide acid) (PCLA)-based PUs [23], were prepared with useful shape-memory properties. 

Since most applications of PLA-based materials are in the sohd state, flie detailed knowledge of the composition, bulk structure, and conformation of these materials is crucial. For example, it is weU known that poly(L-lactide) (PLLA) obtained from LL-lactide is usually molded at 100-120 C in industrial melt processing because of the higher crystallization rate. It has been reported that when it is crystallized within this temperature region a mixture of crystals, a- and P-forms, is formed [2]. Although infrared and Raman spectroscopy is a very promising analytical technique, as will be... 

Poly(L-lactide) (PLLA) is a biodegradable aliphatic polyester produced by ring-opening polymerization of lactide (i.e., with cyclic dimer of lactic acid) or by polycondensation of lactic acid. Although PLLA is a synthetic polymer, it is considered a renewable and bio-based plastic because its raw material lactic acid is synthesized from biomass or renewable resources such as sugars and starch. PLLA has some properties that are similar to some petroleum-based plastics, thereby making it suitable for a variety of applications in the medical, textile, and packaging industries. 

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