Abstract：
In situ forming poly(dimethylaminoethyl methacrylate-co-glycidylmethacrylate)/Chitosan, P(DMAEMA-co-GMA)/Chitosan, (PDG/CS) cryobeads based on \"dropwise freezing into cryogenic liquid method\" combined with \"blending with polymer method\" are promising for applications due to their pH-responsiveness and stability under physiological conditions. Based on classical contact mechanics, Hertzian elasticity of semi-interpenetrated network (semi-IPN) cryobeads was analyzed to examine whether there is a direct correlation between elastic properties of single particle and its macroscopic behavior. A one-step procedure has been proposed to design chitosan-interpenetrated cryobeads with a cationic nature via combination of structural properties as well as functionality of chitosan containing primary and secondary hydroxyl and amino groups. The study is focused on characterization of network formation kinetics in different shapes and how different production variables affect the elasticity/swelling performance of cross-linked system. The elastic properties of semi-IPN cryobeads were improved by both adding chitosan to copolymer PDG structure and lowering the gelation temperature to cryogelation conditions. The results obtained highlighted the importance of composition to modulate elasticity, the influence of preparation temperature and shape of cryobeads on their elasticity. Findings regarding the topography-dependent local elastic properties of chitosan-incorporated semi-IPN gels offer possibilities for modulating the behavior of chitosan-based soft materials.
摘要：
原位形成聚（甲基丙烯酸二甲基氨基乙酯-共-甲基丙烯酸缩水甘油酯）/壳聚糖，P（DMAEMA-co-GMA）/壳聚糖，（PDG/CS）基于“逐滴冷冻成低温液体方法”与“与聚合物共混方法”相结合的冷冻珠由于其在生理条件下的pH响应性和稳定性而有望应用。基于经典接触力学,分析了半互穿网络（半IPN）冷冻珠的赫兹弹性，以检查单个颗粒的弹性与其宏观行为之间是否存在直接相关性。已经提出了一种一步程序来设计具有阳离子性质的壳聚糖互穿冷冻珠，方法是结合结构特性以及包含伯羟基和仲羟基和氨基的壳聚糖的功能。该研究的重点是表征不同形状的网络形成动力学以及不同的生产变量如何影响交联系统的弹性/溶胀性能。通过将壳聚糖添加到共聚物PDG结构中并将凝胶化温度降低到冷冻凝胶化条件，可以改善半IPN冷冻珠的弹性性能。获得的结果强调了成分调节弹性的重要性，冷冻珠的制备温度和形状对其弹性的影响。有关掺入壳聚糖的半IPN凝胶的形貌依赖性局部弹性特性的发现为调节壳聚糖基软材料的行为提供了可能性。
