聚环氧丙烷聚氨酯／聚（甲基丙烯酸甲酯—苯惭烯）IPN的研究

改变聚（甲基丙烯酸甲酯－苯乙烯（Ｐ（ＭＭＡ－ｃｏ－Ｓｔ）中 甲基丙烯酸甲酯的含量（ＷＭＭＡ），通过一步法合成出聚环氧氯丙烷聚氨酯（ＰＵ（ＰＥＣＨ）／Ｐ（ＭＭＡ－ｃｏ－Ｓｔ）ＩＰＮ．ＤＳＣ、ＴＥＭ和动态粘弹谱研究结果表明：当Ｐ（ＭＭＡ＿ｃｏ－Ｓｔ）中ＷＭＭＡ大于０．６时，ＩＢＮ仅有一个Ｔｇ；当ＷＭＭＡ小于０．４时，ＩＰＮ有２个Ｔｇ，ＴＥＭ上出现相区，Ｐ（ＭＭＡ－ｃｏ－Ｓｔ）深度参数（δ）及δ的氢键作     

聚二甲基硅氧烷改性的聚氨酯齐聚物增韧环氧树脂

聚二甲基硅氧烷改性的聚氨酯齐聚物增韧环氧树脂;聚氨酯齐聚物;聚二甲基硅氧烷;环氧树脂;增韧;IPN     

聚环氧氯丙烷聚氨酯／聚甲基丙烯酸甲酯IPN力学性能

利用改变组成比、聚氨酯ＰＵ软段的分子量、Ｒ值、异氰酸酯和两网络各自交联剂含量合成出５个系列的聚环氧丙烷聚氨酯／聚甲基丙烯酸甲酯互穿聚合物网络，利用ＩＰＮ中交联、互穿、缠结程度的不同，并结合ＤＣＳ、ＴＥＭ、动态粘弹谱讨论了ＩＰＮ力学性能。     

新型聚二甲基硅氧烷聚脲聚氨酯磺酸型离聚体的合成及性能（Ⅰ）

采用氨丙基封端的聚二甲基硅氧烷,与4,4’-二异氰酸酯二苯甲烷反应,以1,2-二羟基丙磺酸钠为扩链剂合成了一系列结构规整,软段分子量不同的新型聚二甲基硅氧烷聚脲聚氨酯离聚体,并进一步利用阳离子交换树脂将磺酸钠转换为其它金属盐。采用示差扫描量热计,付里叶变换红外光谱,动态力学谱,光电子能谱仪,热失重分仪及应力应变测试仪研究了其形态结构和性能。     

聚氨酯／聚甲基丙烯酸甲酯互穿聚合物网络的研究

本文对(蓖麻油-聚乙二醇)聚氨酯/聚甲基丙烯酸甲酯(PU/PMMA)互穿聚合物网络(IPN)体系进行了研究.实验结果表明:IPN的力学性能受网络化学构型控制.在PU/PMMA为25/75时,应力-应变曲线出现屈服点,产生类似皮革行为,并在此点抗张强度最高,表现明显的协同效应.动态力学性能及电镜均证明该体系相分离十分严重,通过加入扩链剂及网间交联剂能显著改善两组分相容性,其中网间交联剂效果最好。     

水性聚氨酯-聚丙烯酰胺IPN水凝胶的合成及性能

水性聚氨酯(WPU);聚丙烯酰胺(PAAm);互穿网络(IPN);水凝胶;抗菌     

氨乙基氨丙基聚二甲基硅氧烷改性聚氨酯的研究

在无溶剂条件下合成了一系列氨基硅油改性聚氨酯,并对材料的力学性能、耐热性、疏水性及微观形态进行了研究。结果表明：改性后的聚氨酯具有更优良的力学性能、耐热性及表面疏水性,且材料呈微观相分离形态。     

丙烯酸松香蔗糖聚氨酯/聚丙烯酸酯IPN的合成与性能

丙烯酸松香蔗糖聚氨酯/聚丙烯酸酯IPN的合成与性能     

端羟基聚丁二烯型聚氨酯/聚苯乙烯(或聚甲基丙烯酸甲酯)互穿网络的形态和玻璃化转变

The morphology structure and glass transition behavior of polybutadiene-based polyuretha-ne/polystyrene (or polymethyl methacrylate) interpenetrating polymer network (PU(HTPB)/ PSt-IPN, PU(HTPB)/PMMA-IPN) were investigated by TEM and DSC. TEM showed that the phase inversion of PU(HTPB)/PSt-IPN occurred in the concentration of 25% PU(HTPB), and the size of dispersed phase domains of the IPN formed was smaller in the concentration about 50% PU(HTPB). Increasing DVB content or proportion of NCO to OH enhanced in-terpenetration of two components. All of IPN samples exhibited special cellular structure. According to the fact that PU(HTPB) was formed first,a formation mechanism of the struc-ture was proposed.     

淀粉和生物降解大分子间的半互穿聚合物网络的耐水性研究

以淀粉和可生物降解的PCL或PHBV等疏水性脂肪族聚酯为原料, 制备了淀粉基的Semi-IPN材料. 加入PCL或PHBV等疏水性大分子的使淀粉基Semi-IPN材料的耐水性能相对于原淀粉有很大的改善, 通过热处理和溶剂化作用能使Semi-IPN的耐水性进一步提高.     

磁性半互穿网络智能水凝胶的合成及性质评价

以甲基丙烯酸(MAA)、N-异丙基丙烯酰胺(NIPAAm)、丙烯酰胺(AM)为原料,N,N′-亚甲基双丙烯酰胺(MBA)为交联剂,利用IPN技术并结合磁性的γ-Fe₂O₃增强剂,在水溶液中制备了半互穿网络水凝胶(PMAA/PAM-NIPAAm/γ-Fe₂O₃),研究了水凝胶的溶胀性﹑热稳定性和电磁性。实验表明,水凝胶形成稳定的IPN互穿网络结构且该水凝胶具温度、pH双重敏感性和顺电磁性。所合成的水凝胶在低临界溶解温度31℃以下,具有明显正向温敏性,高于此温度,水凝胶的温度敏感性会逐渐减弱。产品成功克服了NIPAAm类水凝胶的温缩性。     

高强度PAM/PVP半互穿网络凝胶制备及力学性能

以过硫酸铵为引发剂通过一步溶液聚合制备了由化学交联的聚丙烯酰胺(PAM)与聚乙烯吡咯烷酮(PVP)贯穿形成的PAM/PVP半互穿网络(semi-IPN)凝胶,着重研究了凝胶的机械性能。红外光谱、热重分析及拉伸实验分析可知PAM与PVP之间存在氢键作用。拉伸实验表明:在PAM中引入PVP,凝胶拉伸强度明显提高,m(PVP)/m(AM)=7.51%时制备的PAM/PVP semi-IPN凝胶拉伸强度比单纯化学交联的PAM增大64.67%;当AM=6mol/L,n(MBA)/n(AM)=1.67×10-4,m(PVP)/m(AM)=7.51%时,制备的凝胶机械性能较好,拉伸强度达到1.84MPa,断裂伸长率可达3322%;随着含水率增加,凝胶拉伸强度及断裂伸长率均有所降低。     

Permeability of the outer membrane of bacteria.

The outer membrane of Gram-negative bacteria is an attractive system for the study of the structure-function relationships in biological membranes. This membrane has, inter alia, the task of regulating the inflow of nutrients and outflow of waste products. Investigations with the aid of mutants showed that there are at least two general pathways for the diffusion of small molecules across the outer membrane: one for hydrophobic and one for hydrophilic compounds. In the case of the “hydrophobic pathway” the hydrophobic compound dissolves in the interior of the membrane and then crosses the membrane in accordance with the partition coefficient. In wild-type forms of enteric bacteria this pathway cannot be used—presumably owing to the absence of regions with phospholipid bilayers. Small hydrophilic molecules, on the other hand, penetrate the membrane through water-filled pores.     

多孔岩心的渗透性

The relaxation properties of water saturated in porous core are discussed and the distribution of proton transverse relaxation time and bi-exponential model of longitudiual relaxation time are obtained, which provide an illustration for two-model of fluids saturated in porous media. The cutoff value of T_1 based on relaxation specific property of fluids in porous core is adopted to improve the correlation between permeability and ?4T1b2.     

联苯二酐型聚酰亚胺的透气性能与分子结构关系的研究

联苯二酐型聚酰亚胺的透气性能与分子结构关系的研究李悦生，丁孟贤，徐纪平（浙江大学高分子科学与工程研究所，杭州，３１００２７）（中国科学院长春应用化学研究所）关键词聚酰亚胺，膜，气体分离，透气性，透气选择性联苯二酐（ＢＰＤＡ）型聚酰亚胺具有较高的透气选...     

多环芳二酐型聚酯亚胺膜的透气性能

多环芳二酐型聚酯亚胺膜的透气性能李悦生，丁孟贤，徐纪平（浙江大学高分子科学与工程研究所，杭州，３１００２７）（中国科学院长春应用化学研究所）关键词聚醚酰亚胺，聚酯酰亚胺，膜，透气性通常的聚酰亚胺加工性能较差，在芳环二酐的苯环间引入醚键等柔性基团后，其...     

Pore Modification in Porous Ceramic Membranes With Sol-Gel Process and Determination of Gas Permeability and Selectivity

Summary: The aim of the study was to investigate the variation in total surface area, porosity, pore size, Knudsen and surface diffusion coefficients, gas permeability and selectivity before and after the application of sol-gel process to porous ceramic membrane in order to determine the effect of pore modification. In this study, three different sol-gel process were applied to the ceramic support separately; one was the silica sol-gel process which was applied to increase porosity, others were silica-sol dip coating and silica-sol processing methods which were applied to decrease pore size. As a result of this, total surface area, pore size and porosity of ceramic support and membranes were determined by using BET instrument. In addition to this, Knudsen and surface diffusion coefficients were also calculated. After then, ceramic support and membranes were exposed to gas permeation experiments by using the CO₂ gas with different flow rates. Gas permeability and selectivity of those membranes were measured according to the data obtained. Thus, pore surface area, porosity, pore size and Knudsen diffusion coefficient of membrane treated with silica sol-gel process increased while total surface area was decreasing. Therefore, permeability of ceramic support and membrane treated with silica sol-gel process increased, and selectivity decreased with increasing the gas flow rate. Also, surface area, porosity, pore size, permeability, selectivity, Knudsen and surface diffusion coefficients of membranes treated with silica-sol dip coating and silica-sol processing methods were determined. As a result of this, porosity, pore size, Knudsen and surface diffusion coefficients decreased, total surface area increased in both methods. However, viscous flow and Knudsen flow permeability were detected as a consequence of gas permeability test and Knudsen flow was found to be a dominant transport mechanism in addition to surface diffusive flow owing to the small pore diameter in both methods. It was observed that silica-sol processing method had lower pore diameter and higher surface diffusion coefficient than silica-sol dip coating method.     

亲水/疏水半互穿网络凝胶对温度的响应

研究了一种亲水/疏水型半互穿网水凝胶（PAAc/QPVPD gels）对温度的刺激响应.在弱酸性或弱碱性（pH=7.5）溶液中,该凝胶的溶胀比在低温区（< 28 ℃）随温度的升高微微增大,约在28 ℃出现最大值,然后随温度升高而迅速减小,温度约为32.5 ℃时溶胀比趋于最低值.这主要是由于聚丙烯酸网络(PAAc)中氢键的解离与疏水改性聚电解质N-正十二烷基聚（4-乙烯吡啶）溴化盐(QPVPD)的疏水相互作用共同引起的.     

双醚二酐型聚醚酰亚胺的透气性能与分子结构之间关系的研究Ⅰ

合成了一系列双醚二酐型聚醚酰亚胺（ＰＥＩ），研究了它们对Ｈ２、ＣＯ２、Ｏ２、Ｎ２和ＣＨ４五种气体的透过性能与分子结构的关系．结果表明，这类聚醚酰亚胺的分子结构对其透气性和透气选择性有很大的影响，聚合物的自由体积和链段活动性是控制透气性和透气选择性的主要因素。三种带有酰亚胺键邻位取代基的聚醚酰亚胺（ＨＱＤＥＡ—ＤＭｏＢＤＡ、ＨＱＤＥＡ—ＤＭＭＤＡ和ＨＱＤＥＡ—ＤＭｏＭＤＡ）具有较大的自由体积和较小的链段活动性、很高的透气性和透气选择性。