Organic Polymeric Materials Used in Implants

Polymers are made of large molecules that consist of a many monomers fused together through chemical bonds to make a strong material. Certain polymers are made of different chemical compositions of different molecular weights, crystallization, different degrees of hydrophobic characteristics, and heating transformations. Polymer materials are utilized for their slow degradable capabilities, ability to influence new formation of bone tissue, and contain porosity for cells to latch onto and utilize. The drawback of using polymeric materials in implants is that the properties of the material are unable to support a sufficient amount of mechanical load that is required. A disadvantage to using polymeric material is that during the process of sterilization it can easily change the properties of the material. Some polymers such as Polymethylmethacrylate (PMMA) can be toxic to the body causing heat damages to tissue cells. PMMA may not generally be degradable in the body but release particles known as debris that can lead to inflammation to the surrounding tissue of the implant. PLGAs are known for not causing inflammation to the bone tissue and are highly biocompatible. These polymers induce production of osteoblast in surrounding bone tissue of the implant. (Dorozhkin, 2009) (6)

A polymeric material that is used for prosthesis is D, L-polylactic-polyglycolic acid (PLGA)/L-polylactic acid (L-PLA). This polymeric material is a copolymer that is comprised of three fourths of polylactic acid and one fourth of polyglycolic acid. Another type of PGLA copolymer is made of thirty percent of polyglycolic acid and seventy percent of polylactic acid. Poly lactic acid (PLA) is a polymer that is thermoplastic that has an amorphous structure. L(-)-...

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...catalyst of an inert material roughly around 200˚C under minimal pressure. In order to produce high density polyethylene, propene it is placed into solvent that is inert such as heptane. Heptane contains a compound of trialkyl alumina and titanium. (answers.com) (:( sorry) (12) The resultant is a mixture of both istactic and atactic material. The physical property of PP utilizes young’s modulus as it may vary. Rubber particles are incorporated into PP to give it the characteristics of stiffness and elasticity. PP are more favored than other plastics due to its rigidity and low costs for production. The melting point for this material is 160˚C, which is higher than other plastics. Being that PP has a high melting point it makes it more heat resistant.

Works Cited

(Castleman, 1976), (Kapanen, 2002), (Henton, 2005), (Dorozhkin, 2009), (Wahl, 2006), answers.com