蓖麻油聚氨酯／聚取代乙烯互穿网络聚合物作为带锈涂料及粘合剂的可能性

在室温用氧化还原引发剂将蓖麻油、甲苯二异氰酸酯及取代乙烯合成了蓖麻油聚氨酯／聚取代乙烯互穿网络聚合物（ＩＰＮ），研究了不同组成对带锈铁板搭接剪切强度的影响。指出搭接剪切强度随取代乙烯均聚物的玻璃化温度增加而增。ＮＣＯ／ＯＨ之比愈大，搭接剪切强度也愈大。以蓖麻油聚氨酯／（丙烯腈－苯乙烯）共聚物的反应液作为带锈铁板的涂料，其涂膜性能良好。用扫描电镜观察了此种涂料与带锈铁板的结合状态，并讨论其成因。     

高交联大孔苯乙烯—二乙烯苯共聚物的磺化反应

研究了高交联大孔苯乙烯－二乙烯苯共聚物在有溶胀剂和无溶胀剂条件下,反应温度、反应时间及共聚物合成时所用致孔剂对其磺化反应的影响。结果显示,当磺化反应在不同溶胀剂介质中进行时,共聚物的交换容量随交联度变化可呈现不同的关系。与低交联大孔共聚物（交联度７％）比较,高交联大孔共聚物（交联度６０％）磺化反应速度更快,反应能在低得多的温度下进行,同时溶胀介质对磺化产物的交换容量的影响变得很小。６０％交联的共聚     

蓖麻油聚氨酯和乙烯类聚合物互穿网络材料的生成特点及其动态力学性能

研究蓖麻油聚氨酯/取代乙烯共聚物的互穿网络物(IPN)的生成特点指出,其中取代乙烯游离基共聚的氧化还原引发剂组份-过氧化苯甲酰或二甲基苯胺都能加速聚氨酯网络(Pu)的生成。反应温度在 30℃以上蓖麻油也能参与游离基共聚。蓖麻油不仅与TDI反应生成Pu网络,而且也有小部分参与取代乙烯共聚物长枝链的形成。Pu网络的形成较长枝链的生成为快。生成Pu网络时所放出的热促进取代乙烯与少量蓖麻油的双键共聚,最后生成的IPN不溶于甲苯。这表明生成的是接技的半IPN,而不是单纯的半IPN。动态力学研究指出,包含聚苯乙烯或聚甲基丙烯酸甲酯的这种IPN呈现二个T_g,而只包含聚丙烯腈的仅一个T_g,说明后一IPN中相容性较好,有较多的分子混合。随着聚氨酯与聚取代乙烯的比例减少,二个T_g间的差距减少,而较高温度的T_g随取代乙烯共聚物中丙烯腈含量增加而变小。     

高交联大孔苯乙烯-二乙烯苯共聚物的磺化反应

研究了高交联大孔苯乙烯－二乙烯本共聚物在有溶胀剂和无溶胀剂条件下,反应温度、 反应时间及共聚物合成时所用致孔剂对其磺化反应的影响．结果显示,当磺化反应在不同溶胀 剂介质中进行时,共聚物的交换容量随交联度变化可是现不同的关系．与低交联大孔共聚物（交 联度７％）比较,高文联大孔共聚物（交联度６０％）磺化反应速度更快,反应能在低得多的温度下 进行,同时溶胀介质对磺化产物的交换容量的影响变得很小．６０％交联的共聚物于３５Ｃ反应３ｈ, 可获得接近于表面磺化的产物．     

蓖麻油聚氨酯／乙烯类聚合物交联共聚物的动态力学性能

本文研究了蓖麻油聚氨酯(COPU)/聚甲基丙烯酸丁酯(PBMA)交联共聚物(简称ABCP)的动态力学性能,并将其与COPU/PBMA,IPN的动态力学性能作了比较。发现在ABCP中两组份的阻尼峰互相叠加,形成半相容体系,而在IPN中阻尼峰有个宽的平台。透射电镜照片表明,IPN具有更大的相区结构。这些结果证明,化学交联比物理缠结具有更大的强迫互容性。通过对COPU/乙烯类聚合物(VP)交联共聚物相容性的研究,可知COPU/PBMA,COPU/PST和COPU/PMMA交联共聚物,在动态力学性能上是半相容体系,而COPU/PMA和COPU/PBA交联共聚物是互容体系。     

不同异氰酸酯固化的蓖麻油／酚氧树脂聚氨酯的力学性能

以ＢＦ３·ＯＥｔ２为催化剂，４，４－二羟基二苯基丙烷与环氧氯丙烷反应，生成端羟基的酚氧树脂（Ａ），Ａ与蓖麻油（Ｂ）混合，用３种异氰酸酯（ＴＤＩ、ＩＰＤＩ和ＨＤＩ）作为固化剂，制得交联聚氨酯。研究了这３种聚氨酯的力学性能及形态与组成和二异氰酸酯结构的关系；改变ＮＣＯ／ＯＨ摩尔比及Ｂ与Ａ的质量比，可以制得具有较好力学性能的聚氨酯材料。蓖麻油，酚氧树脂，聚氨酯，力学性能     

智能性共聚物水凝胶P（AM－NaA）相转变的研究

本文用￣（６０）Ｃｏ－ｙ射线辐射合成了聚（丙烯酰胺－丙烯酸钠）Ｐ（ＡＭ－ＮａＡ）智能性共聚物水凝胶，并用ＦＴＩＲ对共聚物进行了表征。着重研究了水凝胶在丙酮－水介质中的溶胀和收缩速率、溶胀平衡时间及体积相转变特性。     

光交联法合成新型温敏性水凝胶的研究

合成了丙烯酸β－羟基丙酯（β－HPAT）－N－肉桂酰氧甲基丙烯酰胺（CMMAM）共聚物，采用光交联法制备了温敏性共聚水凝胶，实验结果表明：共聚物交联程序随光照时间延长而增大，在一定温度范围内，水凝胶的溶胀率（SR）随温度升高而减小，表现出显著的温敏行为。     

聚甲基丙烯酸甲酯混合溶剂体系 Ⅳ.交联聚合物在混合溶剂中的溶胀

一微有交联的聚甲基丙烯酸甲酯试样在甲苯-乙醇和丙酮-水混合溶剂中的平衡溶胀比用容量法作直接测量,当非溶剂的体积分数分别为γ=0.17(乙醇)和0.02(水)时,平衡溶胀比均出现极大,与在稀溶液中的粘度和渗透压行为完全一致.在θ溶剂中的平衡溶胀比Q_θ是与溶剂-非溶剂对无关的常数,因而溶胀数据可以用一维溶胀因子X_(溶胀)= (Q/Q_θ)~(1/3)表示.从实验结果得到聚甲基丙烯酸甲酯的溶度参数δ=10.0.     

智能性共聚物水凝胶P（AM—NaA）相转变的研究

本文用＾６０Ｃｏ－γ射线辐射合成了聚（丙烯酰胺－丙烯酸钠）Ｐ（ＡＭ－ＮａＡ）智能性共聚物水凝胶，并用ＦＴＩＲ对共聚物进行了表征。着重研究了水凝胶在丙酮－水介质中的溶胀和收缩速率、溶胀平衡时间及体积相转变特性。     

三烯丙基异氰尿酸酯交联共聚物的研究(Ⅱ)——醇解物的制备、结构及其性能

将醋酸乙烯酯与三烯丙基异氰尿酸酯共聚物进行皂化制得含有羟基和羧基盐的共聚物以增强共聚物的亲水性,用作气相色谱固定相,考察了不同交联度对皂化反应的影响,测定了皂化后共聚物的孔结构参数及溶胀性能,并对该固定相的色谱性能进行评价。     

苯乙烯-二乙烯基苯模型网络的溶胀

本文对阴离子嵌段共聚的苯乙烯-二乙烯基苯交联网络在良溶剂中的文献溶胀数据作了理论的重新分析,指出这类网络是一种典型的符合两相结构图象的模型网络.将重新处理的文献实验数据与现有溶胀理论作了对比.结果表明,平衡溶胀的统计热力学理论适用于交联密度较高(M_c≤3×10~4)的区间,而标度理论适用于交联密度较低(M_c≥3×10~4)的区间.     

Thermosensitive superabsorbents based on poly(N,N-diethylacrylamide-co-sodium acrylate)

A series of poly(N,N-diethylacrylamide-co-sodium acrylate) with a degree of crosslinking of 1 mol%have been prepared as thermosensitive superabsorbents for water.The critical swelling temperatures or the volume phase transition temperature(VPTT) and the water absorption capacity of the polymers can be modulated by varying the amount of sodium acrylate(0-60 mol%) in the copolymers.The water absorption and swelling properties of the different hydrogels have been studied as function of temperature.The crosslinked copolymers can absorb large amounts of water at ambient temperatures and dehydrate at higher temperatures with relative ease,making the absorbent materials thermally responsive and thus reusable.The water absorption capacity of the copolymers depends on the pH of the media as the acrylate monomer has a higher water absorption in its deprotonated state.Added urea in the media raises and sharpens the VPTT values of the copolymers containing sodium acrylate.     

Temperature-responsive swelling and deswelling of the copolymers from vinyl ether of ethylene glycol and butyl vinyl ether

Linear and crosslinked copolymers of a vinyl ether of ethylene glycol (2-hydroxyethyl vinyl ether, ( 1 )) and butyl vinyl ether ( 2 ) are synthesized by α-irradiation polymerization. It is shown that the linear copolymers exhibit a phase separation phenomenon in dependence of the temperature due to the destruction of hydrogen bonds and the enhancement of hydrophobic interaction in aqueous solution. The processes of reversible swelling or shrinking upon temperature change are demonstrated for polymer networks.     

聚合物微观结构对聚合物电解质膜性能的影响

聚合物的微观结构是设计具有优异的电化学性能的聚合物电解质膜(PEMs)的基础.在电解质膜中,相分离结构形成的离子簇和离子通道可以影响膜在高温低湿度条件下的离子传导和水的传输,这种结构形成的形貌也可以影响膜的吸水率、溶胀度、碱稳定性等性能.近几年来,人们对于具有微观相分离形貌的PEMs的合成和形貌开展了很多研究.本文主要...     

Macroreticular resins. III. Formation of macroreticular styrene–divinylbenzene copolymers

Experimental evidence is presented that describes the mechanism of formation of macroreticular styrene–divinylbenzene copolymers in which phase separation occurs during a suspension polymerization. The mode of formation of the macroreticular structure is described as a three-stage process in which each droplet of the organic phase behaves as an individual in a bulk polymerization that results in a bead of copolymer. Macroreticular structure formation is described by changes in copolymer swelling ratios, infrared absorption spectra of vinyl groups pendent to the polymeric matrices, surface area, total porosity, and pore-size distribution. The proposed mechanism of formation is also substantiated by electron micrographs of the copolymers during various stages of the copolymerization.     

Studies on syntheses and dynamic swelling of pH-sensitive macroporous poly(N-isopropylacrylamide-co-acrylic acid) hydrogels

A series of macroporous poly(N-isopropylacrylamide-co-acrylic acid) (PNIPAm-AA) hydrogels with different composition were synthesized by free-radical copolymerization in the presence of silica particles as a pore generating agent. The equilibrium swelling ratio, half swelling time and dynamic swelling kinetics of the copolymers previously soaked in different acidic buffer solutions were investigated at pH 7 at 25°C. Experimental results revealed that the swelling rate of the macroporous hydrogels was greatly increased compared to conventional hydrogels due to existence of the macroporous structures. It was found that the swelling history of previously putting in acidic solutions copolymers had strong influence on their dynamic swelling kinetics especially for the samples ranging in composition between 30 and 70 mol % of NIPAAm, whereas the swelling history had little influence on the equilibrium swelling ratio of copolymers. The swelling pattern exhibits sigmoid swelling curves. This is explained by an autocatalytic mechanism. The hydrogen bonding dissociation plays an important role in the dynamic swelling behavior.     

Enthalpy of swelling of crosslinked copolymers of acrylic acid β-vinyloxyethylamide in water and ethanol

The thermodynamics of swelling of copolymers of acrylic acid β-vinyloxyethylamide with acrylamide and N-vinylpyrrolidone of various compositions in water and ethanol is investigated. It is established that the swelling of the copolymers in water is characterized by high negative enthalpy values and that the swelling in ethanol is an endothermic process. It is found experimentally that the hydrogels obtained experience contraction at elevated temperatures.     

Partially fluorinated thermally responsive latices of linear and crosslinked copolymers

A series of thermally responsive copolymers of N-isopropylacrylamide (NIPAAM) with a fluorinated hydrophobic comonomer, either hexafluoroisopropylmethacrylate (HFIPMA) or 2,2,3,3,4,4-hexafluorobutylmethacrylate (HFBMA) and a hydrophilic comonomer, methacrylic acid (MAA), were synthesized by emulsion polymerization. The chemical structures of the copolymers were studied by the IR technique. Dynamic light scattering (DLS) showed that aqueous latices of the copolymers exhibited swelling–deswelling changes typical to PNIPAAM; the degree of swelling as well as the temperature at which the polymers collapse depended on the chemical structure of the comonomers. Endotherms related to the contraction of the polymers were studied by differential scanning calorimetry (DSC). A combination of DLS and DSC results revealed that the hydrophobic and hydrophilic units in the copolymers strongly affected the swelling behavior, as well as the local environment of the PNIPAAM chains. The comonomer HFIPMA increased the hydrophobicity of NIPAAM, reduced the swelling, and caused coagulation of the copolymer of NIPAAM and HFIPMA at temperatures above the critical temperature. Hydrophobicity of HFIPMA also affected the rheological properties of the latex. The HFBMA comonomer increased the swelling of the latex particles. Methacrylic acid added into the associating copolymers made the copolymers to show polyelectrolyte behavior with an increase of swelling and a decrease of the enthalpy change upon the collapse. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. B Polym. Phys. 36: 2141–2152, 1998     

Porous structure formation and swelling properties of styrene–divinylbenzene copolymers – effect of diluent nature

The effect of the diluent solvating power on the porosity and swelling properties of styrene–divinylbenzene copolymers was investigated. A mechanism for the swelling of macroporous copolymers in good and poor solvent was proposed. The porous structures were classified according to kinetic data of a poor solvent sorption. When the diluent–copolymer affinity was reduced, the fixed pore volume increased, but the nuclei swelling and the elasticity of internuclear chains diminished.