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1.
(甲基)丙烯酸双环戊烯基酯的除臭研究   总被引:1,自引:0,他引:1  
提出了一种消除DCP( 双环戊二烯) 与DCP(M) A ( 甲基丙烯酸双环戊烯基酯) 恶臭的新方法。  相似文献   

2.
酯化反应合成丙烯酸双环戊烯基酯   总被引:1,自引:0,他引:1  
以双环戊二烯、丙烯酸、水为原料,采用两步法合成丙烯酸双环戊二烯基酯。首先以硫酸为催化剂,双环戊二烯经过水合制得羟基双环戊烯,再以羟基双环戊烯和丙烯酸为原料经过酯化反应得到丙烯酸双环戊二烯基酯与传统的以双环戊二烯与丙烯酸为原料直接加成生成丙烯酸双环戊二烯基酯的工艺相比,减轻了后续的处理工作,提高了产品收率。酯化反应的优化条件为:n(丙烯酸):n(羟基双环戊烯)为1.1、催化剂二丁基氧化锡用量2.5%(质量分数,以羟基双环戊烯质量为基准,下同)、阻聚剂对羟基苯甲醚用量0.1%、带水剂为50%(其中环己烷用量为20.0%、甲苯用量为30%)、反应温度为99℃,反应时间是4h。在此条件下合成的丙烯酸双环戊烯基酯的收率达92%以上,纯度达94.4%。  相似文献   

3.
以丙烯酸和双环戊二烯为原料合成了丙烯酸双环戊烯基酯。实验结果表明:以三氟甲磺酸为催化剂,反应温度为90℃,丙烯酸与DCPD摩尔比为1.1∶1,催化剂用量为反应液总质量的0.1%,反应时间为4h、搅拌速率为200r/min的条件下,DCPD转化率在98%以上,DCPA选择性在95%以上。  相似文献   

4.
本文就DCPA的自由基聚合,分别论述了普通自由基聚合,氧化自由基聚合、紫外光固化、后交联与接枝共聚合的特点与机制,以及它们在生产上的应用。  相似文献   

5.
丙烯酸双环戊烯基酯的光引发与聚合机理的研究   总被引:3,自引:0,他引:3  
通过在有空气和无空气条件下,测定由丙烯酸双环戊烯基酯(CH2=CHCO2-,DCPA)与不同类型光引发剂构成涂膜的光固化时间和分析DCPA及光聚合的不同DCPA聚合物(PDCPA)的红外光谱,提出了DCPA与光引发剂二苯酮(BP)光聚合的一种新反应机理。该机理包括由BP、DCPA的烯丙基氢和氧参予的引发过程,由丙烯酸酯和环戊烯双键参予的链增长过程,以及由高分子自由基和含丙烯酸酯与环戊烯双键的低分子量自由基参予的链终止过程。  相似文献   

6.
紫外光固化丙烯酸双与三环戊烯基酯涂层与其热性能研究   总被引:3,自引:0,他引:3  
经过对丙烯酸双环戊烯基酯(DCPA)与新单体丙烯酸三环戊烯基酯(TCPA)涂层的紫外光固化、固化涂层的DSC分析及从其红外光谱计算得到的聚合物上残余双键的研究,并与丙烯酸异冰片酯(IBA)进行了比较,发现许多新鲜与重要的现象。酯基上含环戊烯双键的DCPA与TCPA,在空气中紫外光固化的速率,大大快于具有饱和酯基的IBA,显示酯基上环戊烯的烯丙位氢具有给氢与除去阻聚的氧的作用。TCPA在空气中紫外光固化速率大大快于DCPA,并且是无臭的。2光固化的PDCPA与PTCPA中存在残余的丙烯酸酯与环戊烯双键,但是光固化的PIBA中没有。双键的残余率,受所用光引发剂的类型与比率及光聚合的氛围影响。光固化的PDCPA与PTCPA可以是交联的。3光固化的PDCPA与PTCPA的DSC图有三个放热峰与一个吸热谷,但光固化的PIBA的DSC图没有放热峰。第一放热峰为所有残余丙烯酸酯双键与部分环戊烯双键聚合热所致。第二放热峰为环戊烯双键聚合热所致。第三放热峰为分解产物燃烧热所致。吸热谷是由于PDCPA与PTCPA分解吸热所致。因此在第一与第二放热峰温度范围内PDCPA与PTCPA进行了再次交联。4光固化的PDCPA的第?  相似文献   

7.
8.
本文合成了甲基丙烯酸二甲胺基乙酯(DM),采用水溶液沉淀聚合法制备甲基丙烯酸二甲胺基乙酯——丙烯腈共聚物;探讨了甲基丙烯酸二甲胺基乙脂与丙烯腈(AN)共聚时,引发剂种类及用量、单体加料方式、聚合反应温度、无机酸等对聚合反应的影响,为制备甲基丙烯酸二甲胺基乙酯——丙烯腈共聚物提供了可行、实用的工艺路线。对合成的产物用红外光谱进行了定性表征。  相似文献   

9.
10.
从丙二酸二乙酯开始,合成了标题化合物3,本文报道了3的合成方法、表征及水解结果。  相似文献   

11.
Due to good reactivity of fluorinated (meth)acrylates with other monomers or polymer segments, fluorinated poly(meth)acrylates possess more economical and convenient synthesis routes than other fluoropolymers. This feature article initially summarizes different types of fluorinated (meth)acrylates, which can be divided into fluorinated alkyl (meth)acrylates and fluorinated aryl (meth)acrylates. Subsequently, various approaches for synthesizing fluorinated poly(meth)acrylates including random, block, graft or star copolymers are described. Conventional free radical polymerization can be used in synthesizing random copolymers, while controlled/“living” radical polymerization can provide well-defined copolymers with accurate control over molecular weight and special structures as expected. In particular, introduction of fluorinated components into as-prepared copolymers offers an alternative route to synthesize fluorinated poly(meth)acrylates which are difficult to be obtained directly via polymerization. The incorporation of fluorine can confer unique and highly desirable properties to poly(meth)acrylates such as low surface energy, thermal stability, chemical and weather resistance, low refractive index, and self-organization characteristics. Such properties are described in great details based on many recent articles.  相似文献   

12.
Summary The bisketeneimine Ph2C=C=N-C6H4-N=C=CPh2 1 has been used as a crosslinker for carboxyl functional (meth)acrylate copolymers of various molar masses, in which the COOH group is attached to the backbone through spacers of various length. The crosslinking reaction, carried out at various temperatures, was monitored by infrared spectroscopy and by dynamic mechanical analysis. From a modelreaction with nonanoic acid kinetic parameters were calculated. The products poly(meth)acrylate-polyimide networks were characterised by NMR and FTIR spectroscopy. The thermal stability (TGA measurement) was comparable to that of a corresponding polyurethane.  相似文献   

13.
(甲基)丙烯酸羟烷基酯合成技术研究进展   总被引:1,自引:0,他引:1  
介绍了(甲基)丙烯酸羟烷基酯的几种合成工艺路线,并对各种工艺路线的优缺点进行了评述,提出了今后的发展方向。对直接开环法所使用的各类催化剂及其优缺点进行了详细的叙述,同时对阻聚剂方面进行了简要的概括。  相似文献   

14.
Coatings of polystyrene and poly(meth)acrylate latices containing alkali-hydrolyzable or nonhydrolyzable cationic emulsifiers on filter papers pretreated with inorganic salts were investigated at room temperature. The surfaces of fibers in the Na2CO3-pretreated papers were coated almost uniformly with the latices containing hydrolyzable emulsifiers. The tendency was more remarkable for polymers with a lower glass transition temperature. Furthermore, thermal annealing at low temperature could improve the surface roughness. These results indicate that hydrolysis of the emulsifier facilitates the coalescence of latex particles and the subsequent polymer adhesion to the paper surfaces, leading to the surface modification.  相似文献   

15.
介绍了一种采用原子转移自由基聚合法在无水无氧状态下制备氯化聚乙烯接枝(甲基)丙烯酸丁酯共聚物的合成工艺,并且利用核磁对产物进行了表征.根据谱图积分面积计算了接枝共聚物中(甲基)丙烯酸丁酯和氯的质量含量.比较了氯化聚乙烯接枝共聚物和氯化聚乙烯对聚氯乙烯冲击性能的增强效果.  相似文献   

16.
Photopolymerizable networks are being explored for a variety of biomedical applications because they can be formed in situ, rendering them useful in minimally invasive procedures. The purpose of this study was to establish fundamental relationships between toughness, network chemical structure, and testing temperature of photopolymerizable (meth)acrylate networks deformed in air and under hydrated conditions. Networks were formed by combining at least one monofunctional (meth)acrylate with a difunctional methacrylate, and weight ratios were adjusted to vary the degree of crosslinking, elastic modulus, and glass transition temperature (Tg). Stress–strain behavior and toughness were determined by performing tensile strain to failure tests at temperatures spanning the glassy and rubbery regimes of each network both in air and phosphate‐buffered saline. In air, all of the networks demonstrated a peak in toughness below the network's Tg. At an “equivalent” test temperature relative to Tg, crosslinking concentration and monomer chemistry influenced the toughness of each network. Apparent toughness is significantly altered in an aqueous environment, an effect driven by water absorption into the network causing the Tg to decrease. The results from this study provide the fundamental knowledge required to guide the development of tougher photopolymerizable networks for mechanically strenuous biomedical applications. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

17.
Thermal polymerization of methyl (meth)acrylate (MMA) was carried out using 2-cyanoprop-2-yl-1-dithionaphthalate (CPDN) and cumyl dithionaphthalenoate (CDN) as chain transfer agents. The kinetic study showed the existence of induction period and rate retardation, especially in the CDN mediated systems. The molecular weights of the polymers increased linearly with the monomer conversion, and the molecular weight distributions (Mw/Mns) of the polymers were relatively narrow up to high conversions. The maximum number-average molecular weights (Mns) reached to 351?900 g/mol (Mw/Mn = 1.47) and 442?400 g/mol (Mw/Mn = 1.29) in the systems mediated by CPDN and CDN, respectively. Chain-extension reactions were also successfully carried out to obtain higher molecular weight PMMA and PMMA-block-polystyrene (PMMA-b-PSt) copolymer with controlled structure and narrow Mw/Mn. Thermal polymerization of methyl acrylate (MA) in the presence of CPDN, or benzyl (2-phenyl)-1-imidazolecarbodithioate (BPIC) also demonstrated “living”/controlled features with the experimented maximum molecular weight 312?500 g/mol (Mw/Mn = 1.57). The possible initiation mechanism of the thermal polymerization was discussed.  相似文献   

18.
A series of methacrylate-crosslinked polymers were investigated as potential polymer electrolytes for energy storage application. Methacrylate ester crosslinkers (25–50 mol.%) with different spacer lengths and MMA as comonomer were polymerised into thin films. Mixtures of ethylene carbonate and propylene carbonate (EC/PC) or alternatively the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM TFSI), both doped with lithium bis(trifluoromethane)sulfonimide (LiTFSI), fulfilled the role of electrolyte and porogen simultaneously. Ionic conductivity increased with increasing porogen content, Li ion concentration, and decreasing amounts of crosslinker (maximum values: 0.5 mS/cm (EC/PC) and 4.5 mS/cm (EMIM TFSI)). Thin films with permanent porosity were obtained for both electrolyte systems. The flexibility of the films increased with a lower concentration of crosslinker or the choice of a crosslinker with a longer spacer. The relationship between pore size, pore morphology, glass transition temperature and ionic conductivity on the other hand was complex and did not exhibit distinct trends. High thermal stability, ionic conductivity and tunable mechanical properties make these polymer thin films attractive candidates as in situ filled Li ion battery separator films either preformed or directly printed.  相似文献   

19.
The purpose of this study was to characterize the partial strain recovery of a thermoset shape‐memory polymer under a constraining stress. Three polymer networks were synthesized from tert‐butyl acrylate and poly(ethylene glycol) dimethacrylate (PEGDMA) solutions. The molecular weight and the weight fraction of the PEGDMA crosslinking monomer was altered systematically to maintain a constant glass transition temperature (Tg = 54°C) but tailorable rubbery moduli, which varied by almost an order of magnitude for the three polymer networks (E = 1.8–11.3°MPa). The shape‐recovery behavior of the polymers under a constraining stress was characterized for programming temperature below (20°C) and above (70°C) the Tg. The experiments revealed a peak in the recovered strain for samples programmed at 20°C. Recovered strain scaled linearly with the constraining stress by the rubbery modulus. The work performed by the shape‐memory polymer networks was observed to be primarily a function of constraining stress and crosslinking density, while programming temperature had a relatively mild influence; however, the efficiency of the shape‐memory effect was shown to be a function of constraining stress and programming temperature, but was independent of crosslinking density. Maximum work efficiencies (up to 45%) were observed for programming temperature of 70°C. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

20.
Free radical solution polymerization of heptadecafluorodecyl acrylate (HDFDA) and heptadecafluorodecyl methacrylate (HDFDMA) was carried out by using 2,2′-azobisisobutyronitrile (AIBN) as the initiator in supercritical carbon dioxide (scCO2). We performed solution polymerization with changing initiator concentration, temperature and polymerization time to study the polymerization kinetics. A nonlinear least square method and dead-end theory were used to determine the constant, K (K=(k p √f)/√k d k d ) and initiator decomposition rate constant (k d ) from experimental data. k d was measured as 3.77 × 10−5 s−1 at 62.7°C for poly(HDFDA) and 2.71 × 10−5 s−1 at 62.5 °C for poly(HDFDMA), respectively, by nonlinear least square method.  相似文献   

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