• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Acta biomaterialia >Effect of soft segment crystallization and hard segment physical crosslink on shape memory function in antibacterial segmented polyurethane ionomers.
【24h】

Effect of soft segment crystallization and hard segment physical crosslink on shape memory function in antibacterial segmented polyurethane ionomers.

机译：软链段结晶和硬链段物理交联对抗菌链段聚氨酯离聚物的形状记忆功能的影响。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Shape memory polyurethane (SMPU) ionomers containing constant 75 wt.% soft segment content were synthesized using poly(epsilon-caprolactone)diol, 4,4'-diphenylmethane diisocyanate, 1,4-butanediol and/or N,N-bis(2-hydroxyethyl)-isonicotinamide. To introduce substrate bonding antibacterial activity, pyridinium was prepared through a neutralization reaction using 1-iodooctane as neutralization agent. For the SMPU ionomer film obtained, tensile testing at 70 degrees C and dynamic mechanical analysis suggests that, at temperatures>T(ms) (the melting point of soft segments), 6.72 and 29.55 mol.% pyridinium within hard segments significantly decreased the mechanical properties such as the stress at 100% elongation (70 degrees C), the initial modulus (70 degrees C) and the elastic modulus (75-110 degrees C). Cyclic tensile investigation demonstrated that the two factors, soft segment crystallization and hard segment physical crosslink, play a very important role in shape memory function in SMPU ionomers. For the each individual specimen, the fixity ratio increased, and the recovery ratio decreased with the extension of cooling time. After sufficient cooling time, the fixity ratio of all specimens can reach a high value (approximately 95%). Owing to the disrupted physical crosslink in the sample containing 29.55 mol.% pyridinium, the crystallization rate of soft segments has less effect on shape fixity. Therefore, a high fixity ratio (93.8%) can be achieved in a short cooling time (30 s). In the control sample, the fixity ratio is only 73.7% after 30 s cooling. In addition, the admirable substrate bonding antibacterial activity of prepared SMPU ionomers was verified using standards AACTT 147 and ASTM E2149 in comparison with the control sample. The antibacterial activity of SMPU ionomers on Gram-positive bacteria (Staphylococcus aureus) is significant, and the rate of reduction of bacteria is 100%; the antibacterial activity on Gram-negative bacteria (Klebsiella pneumoniae) increases from 83.6% to 90.7% with increase in pyridinium content from 6.72 to 29.55 mol.%.
机译：使用聚（ε-己内酯）二醇，4,4'-二苯基甲烷二异氰酸酯，1,4-丁二醇和/或N，N-双（2）合成具有恒定75 wt。％软链段含量的形状记忆聚氨酯（SMPU）离聚物-羟乙基）-异烟酰胺。为了引入结合底物的抗菌活性，通过使用1-碘辛烷作为中和剂的中和反应制备了吡啶鎓。对于获得的SMPU离聚物薄膜，在70摄氏度下进行的拉伸试验和动态力学分析表明，在温度> T（ms）（软链段的熔点）下，硬链段中的吡啶鎓6.72和29.55 mol。％会显着降低机械强度性能，例如在100％伸长率下的应力（70摄氏度），初始模量（70摄氏度）和弹性模量（75-110摄氏度）。循环拉伸研究表明，软链段结晶和硬链段物理交联这两个因素在SMPU离聚物的形状记忆功能中起着非常重要的作用。随着冷却时间的延长，每个样品的固定率均增加，而回收率则下降。经过足够的冷却时间后，所有样品的固定率都可以达到很高的值（大约95％）。由于含29.55 mol。％吡啶鎓的样品中的物理交联被破坏，软链段的结晶速率对形状固定性的影响较小。因此，可以在较短的冷却时间（30 s）内获得较高的固色率（93.8％）。在对照样品中，冷却30 s后的固定率仅为73.7％。此外，与对照样品相比，使用标准AACTT 147和ASTM E2149验证了制备的SMPU离聚物的令人称赞的底物结合抗菌活性。 SMPU离聚物对革兰氏阳性细菌（金黄色葡萄球菌）的抑菌作用显着，细菌的减少率为100％;随着吡啶鎓含量从6.72mol。％增加到29.55mol。％，对革兰氏阴性细菌（肺炎克雷伯菌）的抗菌活性从83.6％增加到90.7％。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号