紫外光同步固化合成互穿聚合物网络研究

A new series of Interpenetrating polymer networks (IPN) was prepared by using both free radical and cationic photoinitiators simultaneously under ultraviolet radiation. The systems studied were castor oil based ure'thane acrylates (Network I) and epoxy resin (Network II) (UV-IPN). In order to compare the effect of different crosslinking operations, urethane-acrylate/ amine cured epoxy resin (AC-IPN) and urethane-acrylate/epoxy-acrylate conetwork (EA-CPN) systems were also synthesized and their dynamic mechanical and stress-strain properties were examined. The results show that UV-IPN exhibits only one Tan δ peak,while two Tan δ peaks can be seen in AC-IPN systems. This suggests that the former is much more compatible than the later.The stress at break was found to increase as epoxy resincomponent increased in both UV-IPN and AC-IPN,while appeared to decrease in EA-CPN as epoxy-acrylate increased.     

紫外光同步固化合成互穿聚合物网络研究

互穿聚合物网络是研制高阻尼材料的理想结构,但从目前国内外文献报道的同步法互穿网络体系来看,由于在制备中采用了两种不同的聚合方法,实际上在形成网络结构的过程中都不是十分理想的同步反应,其反应速度均存在着一定程度的差别。     

含有磺酸和羧酸基团的聚氨酯离聚物的研究

以聚四氢呋喃醚二醇和４，４＇－二苯甲烷二异氰酸酯、二羟甲基丙酸合成了含羧酸基团的聚氨酯，再通过ＮａＨ和丙磺酸内酯接上不同含量的丙磺酸基团。通过ＤＳＣ、动态粘弹谱、应力－应变测试等手段对其形态结构和力学性能进行了研究。结果表明，－ＳＯ３＾－Ｎａ＾＋的引入对ＰＵ离聚物的形态结构有较大的影响。－ＳＯ３＾－含量越高，相分离程度越大；拉伸强度先随－ＳＯ３＾－Ｎａ＾＋含量的增加达到最大值，尔后又下降。材料的亲     

关于开设人际交往课程的一点设想

本文对工学院开设人际交往课程的必要性进行了简要分析，并在此基础上提出了具体实施人际交往课程的目标。     

羧酸型聚乙二醇聚氨酯离聚物及其导电性能

以聚环氧乙烷（ＰＥＯ）为软段，与４，４’－二苯甲烷二异氰酸酯（ＭＤＩ）预聚，以２，２’－二羟甲基丙酸（ＤＭＰＡ）扩链合成了含羧酸基团的聚氨酯，并经中和形成了含不同金属离子的离聚物．测定了样品的热分析数据和力学性能，利用交流阻抗分析仪测定了样品的阻抗谱，由此计算出样品的离子电导率．这类样品由于阴离子（－ＣＯＯ－）固定在聚合物分子链上，因此只有单一阳离子迁移．结果表明，羧酸型聚氨酯离聚物既有较高的单一离子电导率又具有优良的力学性能．讨论了不同软段分子量、硬段含量和金属抗衡离子对离子电导性能的影响     

Enhanced effect of dimension of receptor-ligand complex and depletion effect on receptor-mediated endocytosis of nanoparticles

We present an extended analytical model including the depletion effect and the dimension of ligand-receptor complex,aiming to elucidate their influences on endocytosis of spherocylindrical nanoparticles(NPs). It is found that the dimension of ligand-receptor complex(δ) and the depletion effect interrelatedly govern the optimal conditions of NP endocytosis. The endocytosis phase diagram constructed in the space of NP radius and relative aspect ratio indicates that the endocytosis of NP is enhanced evidently by reducing the optimal radius and the threshold radius of endocytosed NP. Meanwhile, through thermodynamic and kinetic analysis of the diffusion of receptors, the dependence of diffusion length on depletion effect and the dimension of ligand-receptor complex can be identified in great detail. For small aspect ratio, diffusion length decreases with increasing concentration c of small bioparticles in cellular environment. Endocytosis speed corresponding to large radius R and high concentration c of small bioparticles strongly depends on the increasing(2 r-δ). These results may show some highlights into the conscious design of NPs for diagnostic agents and therapeutic drug delivery applications.