Department of Fibre and Polymer Technology, Royal Institute of Technology, Stockholm, Sweden.
Biomacromolecules. 2011 Jun 13;12(6):2382-8. doi: 10.1021/bm2004675. Epub 2011 May 9.
An innovative type of triblock copolymer that maintains and even increases the mechanical properties of poly(l-lactide) (PLLA) and poly(ε-caprolactone) (PCL) with a controlled, predictable, and rapid degradation profile has been synthesized. Elastic triblock copolymers were formed from the hydrophobic and crystalline PLLA and PCL with an amorphous and hydrophilic middle block of poly(but-2-ene-1,4-diyl malonate) (PBM). The polymers were subjected to degradation in PBS at 37 °C for up to 91 days. Prior to degradation, ductility of the PLLA-PBM-PLLA was approximately 4 times greater than that of the homopolymer of PLLA, whereas the modulus and tensile stress at break were unchanged. A rapid initial hydrolysis in the amorphous PBM middle block changed the microstructure from triblock to diblock with a significant reduction in ductility and molecular weight. The macromolecular structure of the triblock copolymer of PLLA and PBM generates a more flexible and easier material to handle during implant, with the advantage of a customized degradation profile, demonstrating its potential use in future biomedical applications.
已经合成了一种新型的嵌段共聚物，它可以维持甚至提高聚（L-丙交酯）（PLLA）和聚（ε-己内酯）（PCL）的机械性能，同时具有可控、可预测和快速降解的特点。弹性嵌段共聚物由疏水性和结晶性 PLLA 和 PCL 以及无定形和亲水性的聚（丁-2-烯-1,4-二基丙二酸酯）（PBM）中间嵌段组成。这些聚合物在 37°C 的 PBS 中降解长达 91 天。在降解之前，PLLA-PBM-PLLA 的延展性大约是 PLLA 均聚物的 4 倍，而模量和拉伸断裂应力保持不变。无定形 PBM 中间嵌段的快速初始水解使微观结构从嵌段共聚物转变为二嵌段共聚物，延展性和分子量显著降低。PLLA 和 PBM 的嵌段共聚物的大分子结构产生了一种更灵活、更易于处理的植入物材料，具有定制降解谱的优势，展示了其在未来生物医学应用中的潜力。
