Polylactic acid synthetic polymers

Braided Synthetic Absorbable Sutures. Suture manufacturers have searched for many years to find a synthetic alternative to surgical gut. The first successful attempt to make a synthetic absorbable suture was the invention of polylactic acid [26023-30-3] suture (15). The polymer was made by the ring-opening polymerization of L-lactide [95-96-5] (1), the cycUc dimer of L-lactic acid. 

Whereas conventional poly (amino acids) are probably best grouped together with proteins, polysaccharides, and other endogenous polymeric materials, the pseudopoly (amino acids) can no longer be regarded as "natural polymers." Rather, they are synthetic polymers derived from natural metabolites (e.g., a-L-amino acids) as monomers. In this sense, pseudopoly (amino acids) are similar to polylactic acid, which is also a synthetic polymer, derived exclusively from a natural metabolite. 

Abstract Synthetic polymers and biopolymers are extensively used within the field of tissue engineering. Some common examples of these materials include polylactic acid, polyglycolic acid, collagen, elastin, and various forms of polysaccharides. In terms of application, these materials are primarily used in the construction of scaffolds that aid in the local delivery of cells and growth factors, and in many cases fulfill a mechanical role in supporting physiologic loads that would otherwise be supported by a healthy tissue. In this review we will examine the development of scaffolds derived from biopolymers and their use with various cell types in the context of tissue engineering the nucleus pulposus of the intervertebral disc. 

In order to decrease human consumption of petroleum, chemists have investigated methods for producing polymers from renewable resources such as biomass. Nature Works polylactic acid (PLA) is a polymer of naturally occurring lactic acid (LA), and LA can be produced from the fermentation of corn. The goal is to eventually manufacture this polymer from waste biomass. Another advantage of PLA is that, unlike most synthetic polymers which litter the landscape and pack landfills, it is biodegradable. PLA can also be easily recycled by conversion back into LA. It can replace many petroleum-based polymers in products such as carpets, bags, cups, and textile fibers. 

Naturally biodegradable polymers produced in nature are renewable. Some synthetic polymers are also renewable because they are made from renewable feedstock, for example polylactic acid is derived from agricultural feedstock. 

Starch-based materials represent the largest class of biodegradable polymer with 44,800 tonnes (including loose-fill foam packaging) consumed in 2005. Excluding loose-fill, starch-based materials amounted to 21,700 tonnes in 2005. Polylactic acid (PLA) is the second largest material class with 35,800 tonnes in 2005, followed by synthetic aliphatic-aromatic copolyesters with 14,000 tonnes. The embryonic PHA category amounts to around 250 tonnes. 

They are made of polymeric, waxy, or other protective materials, that is, biodegradable synthetic polymers and modified natural products such as starches, gums, proteins, fats, and waxes. The natural polymers include albumin and gelatin " the synthetic polymers include polylactic acid and polyglycolic acid. ... 

From the perspective of biocompatibility, degradability, and process-ability, synthetic polymers have many advantages over complex natural polymers such as collagen. One class of polymers in particular, polyesters in the family of polylactic acid (PLA), polyglycolic acid (PGA), and copolymers of lactic and glycolic acids (PLGAs), most closely meets the listed criteria. These polymers have been approved by the FDA for in vivo... 

Polylactic add (PLA) A synthetic polymer formed from lactic acid monomers which degrades by hydrolysis. 

Synthetic polymers (polyvinyl alcohol, polylactic acid,) are very popular due to their higher stability and lower price, but the biocompatible natural polymers are more and more applied, as well as cellular tissue matrices (e.g., bladder submucosa and small intestinal submucosa). 

Synthetic polymers commonly used in numerous biomedical devices offer the distinct advantage of high level of control over the chemical properties of the polymer. As a scaffold for adipose tissue engineering, polylactic acid, polyglycolic acid, and copolymers incorporating both have been widely investigated due to their ability to degrade over... 

In synthetically produced polymers, biodegradability is achieved by reducing the stabilizer content and/or addition of initiators that accelerate biodegradation. Materials in this group include, for example, PHB (polyhydroxybutyrate) and PLA (polylactic acid) [9]. Other polymers use a blend of both types, for example a combination of polyethylene and starch. 

Back to Nature is the solution then Looking at a few numbers in Table 4.7 may prevent hasty judgments reading this questioa About 50 million t of plastics are produced in Europe each year from petroleum. The production of natural polymers is about 0.1% percent of this total virtually all of which is poly lactic acid. These numbers are not promising it would be lunacy to expect that polylactic acid (Fig. 4.30) or any other semi-synthetic and biodegradable polymer could replace petroleum-based plastics in any foreseeable future. 

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