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1.
超支化聚酯的改性及其结晶性能的研究   总被引:11,自引:0,他引:11  
用十六酰氯和十八异氰酸酯分别对端羟基的超支化聚酯BoltornTMH20改性,可获得粉末状超支化低聚物,具有无定形“内核”及可结晶“外壳”的分子结构.实验结果表明,采用十八异氰酸酯改性的丙烯酸化超支化聚酯的熔点高于十六酰氯改性聚合物.  相似文献   

2.
十八烷基三氯硅烷改性超支化聚(胺-酯)吸附亚硝胺的研究   总被引:1,自引:0,他引:1  
以十八烷基三氯硅烷对超支化聚(胺-酯)进行改性,合成了改性的超支化聚(胺-酯)。将改性前后的超支化聚合物用于吸附二甲基亚硝胺和二苯基亚硝胺。吸附结果表明,聚合物对二甲基亚硝胺和二苯基亚硝胺的吸附率分别为51.3%和11.9%,而改性后的超支化聚合物对二甲基亚硝胺和二苯基亚硝胺的吸附率分别为67.3%和37.2%。  相似文献   

3.
王素娟  巴信武 《化学通报》2011,74(3):232-237
两亲性超支化聚合物作为一种新型功能性材料.近年来引起了人们的广泛关注.两亲性超支化聚合物的合成丰要是利用不同亲水性的链段对超支化聚合物端基进行改性,或者首先在超支化聚合物末端产生活性位点,再利用超支化分f作为大分子引发剂引发烯类单体进行斤环聚合、原子转移自由基聚合等得到以超支化聚合物为核的两亲性超支化共聚物;这些分子由...  相似文献   

4.
本文将超支化树脂(HBP)与UV固化粉末涂料相结合,研究了超支化树脂对该涂料的树脂体系玻璃化温度、流变性能及涂膜各项物理性能的影响.结果表明:添加改性与未改性超支化树脂都能降低树脂体系的玻璃化温度,改性超支化树脂不影响体系的流变性能及涂膜性能,未改性超支化树脂可以降低体系粘度但使涂膜性能变差.  相似文献   

5.
以三羟甲基丙烷(TMP)为核,二羟甲基丙酸(DMPA)为支化单体,通过熔融缩聚法合成了第3代端羟基脂肪族超支化聚酯,并用十八酸对其进行端基改性,采用广角X射线衍射(WAXD)、示差扫描量热分析(DSC)及红外光谱(FTIR)研究了不同端基改性程度的超支化聚酯的结晶熔融行为及端烷烃链的构象和堆积结构随温度的变化,采用旋转流变仪研究了端烷烃链对脂肪族超支化聚酯熔体动态黏弹行为的影响.结果表明,这类改性超支化聚酯的结晶归因于长链端烷烃的有序排列,改性程度越高,衍射峰强度越大.受限结晶的端烷烃链在升温后并不能完全转变为无序的结构状态,改性超支化聚酯在"熔点"以上仍有部分有序结构存在.超支化聚酯的线性黏弹区随着端基改性程度的增大而逐渐变短,超支化聚酯的弹性逐渐增大,剪切变稀越明显.动态流变测试中所出现的现象与改性超支化聚酯中端烷烃链的受限密切相关.  相似文献   

6.
全芳型超支化聚酯的合成及端基改性   总被引:6,自引:0,他引:6  
唐黎明 《应用化学》2001,18(4):340-0
芳香聚合物;全芳型超支化聚酯的合成及端基改性  相似文献   

7.
以M_n=250的聚乙二醇二丙烯酸酯为A_2单体(含有两个A基因的单体,其余类推),N-乙基乙二胺为B'B_2单体,利用丙烯酸酯基和胺基的迈克尔加成聚合反应,一锅法合成了表面含丙烯酸酯键、骨架含聚乙二醇(PEG)、内部含叔胺的具有三维椭球状结构的超支化聚酯胺,并研究了其聚合动力学。利用咪唑对超支化聚酯胺进行改性,并初步研究了咪唑改性的超支化聚酯胺的pH响应性和水溶性。利用核磁共振氢谱、红外光谱、凝胶渗透色谱、GPC-MALLS多角度激光散射系统表征了超支化聚酯胺的分子结构和化学组成。结果表明:聚乙二醇链段的引入能够赋予超支化聚酯胺水溶性;咪唑的引入有利于提高超支化聚酯胺的pH响应性。  相似文献   

8.
综述了近年来含磷超支化阻燃剂改性环氧树脂(EP)的研究进展,主要包括含磷杂菲基团超支化阻燃剂、超支化聚磷酸酯阻燃剂、超支化含磷/氮阻燃剂和超支化含磷/氮/硅阻燃剂等其他类型超支化阻燃剂,介绍了不同类型的阻燃剂对EP的阻燃性能和机械性能的影响,并总结对比了添加不同阻燃剂后EP复合材料的阻燃性能、机械性能、玻璃化转变温度(Tg)等性能,最后指明了超支化阻燃剂当前面临的主要挑战并展望了未来的发展趋势。  相似文献   

9.
紫外光固化超支化聚酯的合成及性能   总被引:1,自引:0,他引:1  
张林雅  矫庆泽  赵芸  周明吉  冯薇  葛艳蕊 《化学学报》2011,69(17):2031-2038
以季戊四醇为核,2,2-羟甲基丙酸为臂,采用熔融缩聚法合成并表征了末端含大量羟基的超支化聚酯,其支化度高,黏度低,具有良好的热稳定性.以甲基丙烯酸酐改性超支化聚酯,得到链末端含有C=C的超支化甲基丙烯酸酯,在最佳反应条件下改性反应的转化率可达89%以上.改性后的超支化聚酯表现出更低的黏度,热失重曲线呈现为两段,玻璃态转...  相似文献   

10.
端基对超支化高分子性质影响的研究   总被引:7,自引:1,他引:7  
对端羟基脂肪族超支化高分子的端基进行了乙酰化和硅烷化改性,研究了不同端基对超支化高分子的玻璃化温度,折光指数增量以及特性粘度的影响。结果表明,端基的极性减小使超支化高分子的玻璃化温度降低,不同端基的超支化高分子的折光指数增量也有很大差异,而强极性的端基使超支化高分子在溶液中易产生团聚作用。由于端基在超支化高分子中所占比重较大,端基是影响超支化高分子性质的重要因素。  相似文献   

11.
超支化聚(胺酯)的分子设计及其制备   总被引:21,自引:1,他引:21  
以丙烯酸甲酯和二乙醇胺为原料由Michael加成反应制得N ,N 二羟乙基 3 胺基丙酸甲酯单体 ,再用“准一步法”和“发散法”使之与 1 ,1 ,1 三羟甲基丙烷 (核 )反应合成一种新型超支化聚 (胺 酯 ) .以核磁共振和元素分析方法对N ,N 二羟乙基 3 胺基丙酸甲酯单体的分子结构进行了表征 .GPC测定表明合成的超支化聚 (胺 酯 )分子量分布窄 ,具有单分散性 ;粘度小于同分子量的线形分子 ;耐热性能较好 ,失重温度高于2 0 0℃ .  相似文献   

12.
紫外光固化具有快速反应、室温操作、低能消耗和无溶剂少污染等优点,现正以日益增长的速度应用于涂层和粘合剂等领域。然而,常规的线形光固化齐聚体具有缠结的柔性分子链结构,其粘度随着分子量的增大而快速增加,故其可加工性和应用受到很大的限制。  相似文献   

13.
可光固化星形超支化聚酯的合成与表征   总被引:20,自引:0,他引:20  
描述了基于季戊四醇和1,2,4 苯三甲酸酐,经由甲基丙烯酸缩水甘油酯和甲基丙烯酸酐改性的系列超支化聚酯的“发散”合成方法,即合成反应从“中心核”开始,逐步向外扩展,控制链增长,每个分子形成具有大约8,12和16个甲基丙烯酸酯双键的超支化臂。这种星形聚酯分子具有三维球状结构,不会产生分子链间的缠结,在辐射固化涂层和粘合剂等领域具有广阔的应用前景.  相似文献   

14.
Photo crosslinking due to the photo polymerization of unsaturated acrylic side-groups attached to copolymers of glycidyl methacrylate and methyl methacrylate (GMA-MMA) by reaction with acrylic acid in the presence of benzoin methyl ether as photolabile initiator has been investigated. The composition of these copolymers based on (GMA-MMA, 30:70) were determined by [1H] NMR spectroscopy. The reactivity ratios for the GMA-MMA system were determined using the Kelen-Tüdös method.

The dielectric properties of copolymers based on GMA-MMA acrylate ester (30:70) and homopolymers of MMA in combination with different polyfunctional acrylate ester monomers before and after exposure to UV irradiation have been studied in a solid state matrix, over a frequency range of 100 Hz to 50 kHz and at temperatures in the range 20–70°C.  相似文献   


15.
The UV curable waterborne hyperbranched polyester (WBHP) consisting of a multi-hydroxy functional aliphatic polyester core, which is endcapped with methacrylic and salt-like groups in different ratios was synthesized. The core is second generation of hyperbranched aliphatic polyester Boltorn™ H20 with approximately 16 hydroxyl groups. The effects of different ratios of chemical structure of end groups were studied by evaluating various properties of WBHP such as solubility in water, dynamic viscosity, UV curing rate and final unsaturation conversion. A natural good control over the solubility of the samples was possible by salt-like functionality and raising the temperature. The investigation of solubility characteristics of the modified hyperbranched polyester illustrated that those with higher concentration of salt-like moiety were more soluble while those of having lower salt-like moiety were less soluble. The viscosity of the resin WBHP was reduced rapidly by dilution with water and raising temperature. Water showed a favorable viscosity reduction effect as compared to monomer and its blend with water. The polymerization rate of the resins under UV irradiation in the presence of a photoinitiator showed an increasing trend with higher concentration of methacrylate functionality.  相似文献   

16.
合成了树枝状(甲基)丙烯酸化醚酰胺低聚物,采用拉曼光谱、光-差热分析和动态力学热分析方法对其紫外光固化动力学和固化膜热机械性能进行了研究.结果表明,这种树枝状低聚物在紫外光照下双键转化率可达80%以上,且其最大反应速率、固化膜的软化温度和玻璃化转变温度随双键浓度的增大而提高.  相似文献   

17.
A copolyimide synthesized from 3,3′,4,4′-benzophenone tetracarboxylic dianhydride, 3,5-diaminobenzoic acid, and 2,3,5,6-tetramethyl-p-phenylene diamine was found to be soluble in N-alkyl substituted amides. An organic soluble photosensitive polyimide was obtained by further reaction of the copolyimide with methacrylic acid glycidyl ester. After adding Michler's ketone, the UV spectra absorbance near 360 nm of the copolyimide decreased rapidly upon the irradiation of mercury lamp. Using benzoic acid and methacrylic acid glycidyl ester as model compounds and N, N-dimethylbenzylamine as catalyst, the mechanism of reaction between the carboxylic group of the copolyimide and epoxy group of methacrylic acid glycidyl ester in N-methyl-2-pyrrolidone was found to have two competitive reactions, namely the auto-catalytic and the catalytic reactions. The apparent rate constants of each reaction were determined. Comparison of apparent rate constants between the model compound and the polymer reaction system are also reported.  相似文献   

18.
可聚合的光引发转移终止剂合成接枝共聚物   总被引:4,自引:0,他引:4  
采用一种可聚合的光引发转移终止剂 ,2 N ,N 二乙基二硫代氨基甲酰氧基乙酸 β 甲基丙烯酰氧基乙酯 (MAEDCA) ,通过两种途径制备了含有聚甲基丙烯酸甲酯 (PMMA)和聚苯乙烯 (PSt)链段的接枝共聚物 .其一是将MAEDCA作为引发剂 ,在紫外光照射下引发MMA聚合 ,得到大分子单体 ,通过大分子单体与St的共聚合得到 .考察了所用大分子单体的分子量和浓度对共聚合的影响 .其二是将MAEDCA作为单体与MMA共聚得到侧链上含有N ,N 二乙基二硫代氨基甲酰氧基 (DC)基团的无规共聚物 ,P(MMA co MAEDCA) .在紫外光照射下 ,P(MMA co MAEDCA)作为大分子引发剂引发St聚合 ,得到P(MMA co MAEDCA) g PSt的共聚物 ,研究了接枝共聚合过程的活性自由基聚合特征  相似文献   

19.
Hyperbranched polystyrenes (PS) were prepared by living radical photopolymerization of 4-vinylbenzyl N,N-diethyldithiocarbamate as an inimer under UV irradiation. These hyperbranched PS exhibited large amounts of photofunctional dithiocarbamate groups on their outside surfaces. Subsequently, we derived the star-hyperbranched copolymers by grafting from hyperbranched macroinitiator with t-butyl methacrylate. We obtained poly(methacrylic acid) star-hyperbranched PS nanospheres by hydrolysis of poly(t-butyl methacrylate) grafted chains. We studied in detail two-dimensional nanopattern formation on poly(4-vinylpyridine) (P4VP) or partially quaternized P4VP substrate using such nanospheres by electrostatic interaction.  相似文献   

20.
In this research, we developed a novel and facile strategy to prepare aliphatic tertiary amine chromophore hyperbranched poly(amino ether ester)s with pH and thermo responsiveness via phosphazene base (t-BuP2) catalyzed oxa-Michael addition polymerization of triethanolamine with ethylene glycol diacrylate at room temperature. UV–vis and fluorescence analyses results showed that the tertiary amine at branching point for hyperbranched poly(amino ether ester)s is very important to retain strong blue fluorescence of tertiary amine chromophore. Moreover, the hyperbranched poly(amino ether ester)s exhibit an aggregation caused quenching (ACQ) fluorescence, solvent induced red-shifted emission, molecular weight, and temperature dependent emission characters. More interestingly, the hyperbranched poly(amino ether ester)s show extreme acid induced quenching fluorescence phenomenon, and also display good water solubility, specific recognition of Fe3+ ion, low cytotoxicity, and bright cell imaging, which could serve as a microenvironment-responding fluorescent probe for application in chemical sensing, cell imaging, drug delivery, or disease diagnostics. This research provides a versatile method for the preparation of stimuli-responsive aliphatic tertiary amine chromophore polymers, and supplies ideas for researchers to explore other unconventional fluorescent polymers for application.  相似文献   

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