分段聚异丁烯基热塑性聚氨酯的长期体外生物稳定性。

Long term in vitro biostability of segmented polyisobutylene-based thermoplastic polyurethanes.

机构信息

Department of Chemistry, University of Massachusetts Lowell, Lowell, Massachusetts 01854, USA.

出版信息

J Biomed Mater Res A. 2010 Dec 1;95(3):774-82. doi: 10.1002/jbm.a.32897.

DOI:10.1002/jbm.a.32897

PMID:20725977

Abstract

Long term in vitro biostability of thermoplastic polyurethanes (TPUs) containing mixed polyisobutylene (PIB)/poly(tetramethylene oxide) (PTMO) soft segment was studied under accelerated conditions in 20% H(2)O(2) solution containing 0.1M CoCl(2) at 50 °C to predict resistance to metal ion oxidative degradation (MIO) in vivo. The PIB-based TPUs showed significant oxidative stability as compared to the commercial controls Pellethane 2363-55D and 2363-80A. After 12 weeks in vitro the PIB-PTMO TPUs with 10-20% PTMO in the soft segment showed 6-10% weight loss whereas the Pellethane TPUs degraded completely in about 9 weeks. Attenuated total reflectance Fourier transform infrared spectroscopy confirmed the degradation of Pellethane samples via MIO by the loss of the ∼1110 cm(-1) aliphatic C-O-C stretching peak height attributed to chain scission, and the appearance of a new peak at ∼1174 cm(-1) attributed to crosslinking. No such changes were apparent in the spectra of the PIB-based TPUs. The PIB-based TPUs exhibited 10-30% drop in tensile strength compared to 100% for the Pellethane TPUs after 12 weeks. The molecular weight of the PIB-based TPUs decreased slightly (10-15%) at 12 weeks. The Pellethane TPUs showed a dramatic decrease in M(n) and an increase in low molecular weight degradation product. Scanning electron microscopy (SEM) showed severe cracking in the Pellethane samples after 2 weeks, whereas the PIB-based TPUs exhibited a continuous surface morphology. The weight loss, tensile, and SEM data correlate well with each other and indicate excellent biostability of these materials.

摘要

研究了含有混合聚异丁烯（PIB）/聚四亚甲基醚（PTMO）软段的热塑性聚氨酯（TPU）在 20%H2O2 溶液中 0.1M CoCl2 存在下于 50°C 下的长期体外生物稳定性，以预测体内金属离子氧化降解（MIO）的抵抗力。与商业对照 Pellethane 2363-55D 和 2363-80A 相比，基于 PIB 的 TPU 表现出显著的氧化稳定性。在体外 12 周后，软段中含有 10-20%PTMO 的 PIB-PTMO TPU 显示出 6-10%的重量损失，而 Pellethane TPU 在大约 9 周内完全降解。衰减全反射傅里叶变换红外光谱证实，通过 MIO 降解了 Pellethane 样品，特征是链断裂导致 ∼1110 cm-1 脂肪族 C-O-C 伸缩峰高度降低，以及 ∼1174 cm-1 处出现新的交联峰。在 PIB 基 TPU 的光谱中没有出现这种变化。与 Pellethane TPU 的 100%相比，PIB 基 TPU 在 12 周后拉伸强度下降了 10-30%。PIB 基 TPU 的分子量在 12 周时略有下降（10-15%）。Pellethane TPU 的 M(n) 急剧下降，低分子量降解产物增加。扫描电子显微镜（SEM）显示 Pellethane 样品在 2 周后出现严重开裂，而 PIB 基 TPU 则表现出连续的表面形貌。重量损失、拉伸和 SEM 数据相互关联良好，表明这些材料具有优异的生物稳定性。