摘要:
A method for controlling the gel point of a bone cement containing poly(polypropylene fumarate), a cross-linking monomer, an initiator, an inorganic filler, and a radical initiator. The gel point is controlled by varying the molecular weight of the poly(polypropylene fumarate) while maintaining the weight average molecular weight (M.sub.w) of the poly(polypropylene fumarate) above 2000 and the polydispersity index of the poly(polypropylene fumarate) below 2. In a preferred embodiment, the molecular weight of the poly(polypropylene fumarate) greater than 4000, and more preferably greater than 5000.
摘要:
High molecular weight linear poly(propylene fumarate) having a relatively low polydispersity index by utilizing a relatively pure intermediate and a method for making same. Fumaryl chloride and propylene glycol are reacted in the presence of potassium carbonate. The potassium carbonate present in the reaction solution prevents the acid by-product from catalyzing reactions at the fumarate double bond. The bis(propyl fumarate) produced according to this technique can be transesterified using conventional processing steps to yield P(PF). The P(PF) produced from bis(propyl fumarate) produced according to the present method has a higher molecular weight and is purer than P(PF) produced using previously known techniques.