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1.
Liquid crystal is a material which is between solid and liquid phase and commonly called mesophase. Blends of liquid crystal are of great interest because of their unique optical properties. Blending in this study using two monomers of liquid crystal were cholesteryl acrylate and methyl phenyl benzoyl acrylate. The polymerization process using uv curing techniques by irradiation UV ray and without irradiation UV ray. Polymerization of blending liquid crystal acrylate using initiator 2-hydroxy-2-methyl-1-phenylpropane. Based on peak at GPC curve of polymerization by irradiation UV ray, type of that polymer is copolymer. Therefore the polymerization without UV ray, type of that polymer is homopolymer. SEM images of liquid crystal acrylate polymer showed lamella chain models that are characteristic of a polymer chains. Type of polymer liquid crystal acrylate was the type of Side Chain Liquid Crystalline Polymers (SCLCPs). Therefore acrylate polymer liquid crystal in this research has semi-crystalline phase, which contained crystalline phase and amorphous phase on the XRD pattern. The results of FT-IR spectroscopic characterization of the two monomers showed a peak at the wave number of 1600.43 cm -1 and 1622.86 cm-1 which indicates a double bond (C=C) were obtained from acrylation. While the spectroscopy on the product blending the wave number of the peak regions is reduced that shows that carbon double bonds (C=C) in the acrylate group has polymerized. It also strengthened with a very sharp peak for CC functional groups on the wave number of 2855.15 cm-1. The results of this study indicate that the liquid crystal polymer acrylic polymerization results with radiation UV ray and without UV ray, respectively absorb light in the UV wavelength region 363 nm and 351 nm.  相似文献   

2.
Densities of the ternary system 1,4-dioxane + butyl acrylate + ethyl acrylate and its binary butyl acrylate + ethyl acrylate have been measured in the whole composition range, at 298.15 K and atmospheric pressure, using an Anton Paar DMA 5000 oscillating U-tube densimeter. The calculated excess molar volumes of the binary system are positive and were correlated with the Redlich–Kister equation and with a series of Legendre polynomials. Several models were used to correlate the ternary behavior from the excess molar volume data of their constituent binaries and were found equally good to fit the data. The best fit was based on a direct approach, without information on the component binary systems.  相似文献   

3.
介绍了热固性丙烯酸酯液晶单体的合成路线、取向方式和聚合工艺,叙述了数种影响热固性丙烯酸酯液晶单体及其聚合物性能的主要因素,简要介绍了国内外热固性丙烯酸酯液晶研究的最新动向。  相似文献   

4.
Abstract

Phenylacetylene (PA, M2) and methyl acrylate (Mi) copolymerization can be described by the simple terminal model having the parameters r1 = 0.67 and r2 = 0.11. 1H-NMR spectroscopy shows the predominant trans configuration of PA units, the high tendency of coisotactic alternating addition, and influence of temperature on the chain conformation.  相似文献   

5.
Acrylate–alkyd hybrid latex via miniemulsion polymerizations show promise as water‐borne coating systems. However, poor homogeneity of the particles caused by the immiscibility of the alkyd in polyacrylate limits monomer conversion and film formation. To resolve this problem, the hybrid miniemulsion polymerization of acrylate in the presence of linoleic acid and sunflower seed oil was carried out. Products were characterized by solvent extraction, dynamic light scattering, gel permeation chromatography (GPC), differential scanning calorimeter (DSC), and transmission electron microscopy (TEM). The results provide clear evidence that substituting a fatty acid or natural oil with smaller molecular size (weight) for a conventional alkyd improves the grafting efficiency, and enhances the homogeneity of the hybrid polymer particles in water‐borne latex systems.

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6.
漆酚基环氧丙烯酸酯的合成   总被引:1,自引:0,他引:1  
以漆酚、环氧氯丙烷、丙烯酸为主要原料,通过两步反应合成了漆酚基环氧丙烯酸酯,其结构经IR表征。较适宜的反应条件为:漆酚基环氧树脂(UE)50mmol,n(UE中的环氧基团)∶n(丙烯酸)=1.00∶0.75,w(三乙胺)=2%,于80℃反应3h,丙烯酸的转化率在94%以上。该反应为一级反应,表观活化能52.7kJ.mol-1,频率因子1.719×104s-1。  相似文献   

7.
综述了紫外光固化聚氨酯丙烯酸酯树脂的研究,讨论了其合成方法、固化机理以及性能。  相似文献   

8.
9.
The polymerization kinetics of n-lauryl acrylate have been investigated in ethyl acetate and n-heptane at 40°C. A high monomer order, 1.6(5), was found in both solvents. Corresponding initiator orders, determined using Azdn and lauroyl peroxide, were slightly less than the usual value of 0.5. Although the chain termination reaction is undoubtedly diffusion controlled from the start of polymerization, diffusion effects dependent on monomer concentration only partly account for the high monomer order. Other possible explanations based on primary radical termination, “cage-effects,” degradative chain transfer, and radical complexing are also not applicable. Contrary to observations with lower acrylate esters, autoacceleration effects do not occur in the high conversion polymerization of n-lauryl acrylate. Ths probably reflects the reduced importance of radical branching reactions with this monomer.  相似文献   

10.
Ternary monomer reactivity ratios of triisopropylsilyl acrylate (SiA), methyl methacrylate (MMA), and n‐butyl acrylate (BA), as common monomers in self‐polishing coatings (SPCs) binders are obtained using experimental data collected from free radical bulk polymerization at 70 °C. Different terpolymerizations at low and medium‐high conversions are performed at optimized feed compositions. Estimations are made using the error‐in‐variables model (EVM) framework, applying the recast form of the Alfrey–Goldfinger (AG) model and a direct numerical integration (DNI) approach to the collected data. Estimations from individual low and medium‐high conversion data are compared to those found with the combined data (full conversion range data). The highest certainty in point estimates are obtained with analysis of the full conversion range data. Furthermore, the reactivity ratios determined from the combined data fall between those found with analysis of individual low and medium‐high conversion data, another corroboration of reliable data collection. Reactivity ratios determined from analysis of the combined data (rSiA/MMA = 0.4185, rMMA/SiA = 1.3754, rSiA/BA = 0.8739, rBA/SiA = 0.5736, rBA/MMA = 0.3692, rMMA/BA = 1.7919) are used in the recast AG model to predict cumulative terpolymer composition as a function of conversion. The experimental data and model prediction show satisfactory agreement.  相似文献   

11.
《Analytical letters》2012,45(5):858-866
A procedure was developed for the determination of polyethylene glycol monoester acrylate (PEGMA) and polyethylene glycol diester acrylate (PEGDA) by reversed-phase high performance liquid chromatographic (RP-HPLC) with UV detector. Sample was well separated on an SinoChrom ODS-BP (C-18) column (200 × 4.6 mm i.d., 5 μm) with mobile phases composed of acetonitrile-phosphate buffer solution (0.05 mol · L?1 pH = 6.86) in the ratio of 42:58 (v/v). The PEGMA and PEGDA were detected by UV detector at 205 nm, and quantitatively analyzed with an external standard of methyl acrylate. For PEGMA, the linear response ranged from 0.40 × 10?5 mol · L?1 to 2.00 × 10?3mol · L?1 (r2 > 0.999), the detection limit was 0.12 × 10?5 mol · L?1, the recovery rate was found to be 93.4%–99.7%. For PEGDA, the linear response ranged from 0.20 × 10?5 mol · L?1 to 1.00 × 10?3mol · L?1 (r2 > 0.999), the detection limit was 0.04 × 10?5 mol · L?1, the recovery rate was found to be 99.1% ~ 105.8%. This quantitative method can also be used in the HPLC analysis of other α,β-unsaturated esters.  相似文献   

12.
有机硅改性丙烯酸酯乳液的流变性   总被引:10,自引:0,他引:10  
张力  刘敬芹 《应用化学》2003,20(3):210-0
聚合物乳液;流变性能;反应性乳液;有机硅改性丙烯酸酯乳液的流变性  相似文献   

13.
锌电沉积与丙烯酸盐聚合的复合过程   总被引:4,自引:0,他引:4  
姚素薇  廖川平 《应用化学》1997,14(2):118-118
锌电沉积与丙烯酸盐聚合的复合过程姚素薇廖川平*郭鹤桐(天津大学应用化学系天津300072)关键词电沉积,电聚合,复合镀层,聚合物膜1996-06-07收稿,1996-08-09修回国家自然科学基金资助课题让锌的电沉积与丙烯酸盐的电化学引发自由基聚合[...  相似文献   

14.
Polyurethane acrylate resins cured by two different ways, a thermal way and a photochemical way, are investigated by means of differential scanning calorimetry (DSC) and thermally stimulated depolarization currents (TSDC). Even if both curing methods lead to the same material from a chemical point of view, we show that important differences exist between the thermocured resin and the photocured resin in terms of molecular relaxation behaviour.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

15.
含氟丙烯酸酯光致聚合物的全息特性研究   总被引:1,自引:1,他引:0  
提高记录单体在成膜物中的迁移速率,加大记录单体与成膜物的折射率差,可以实现光致聚合物的折射率空间调制最大化.本工作以高折射率的超支化聚酯(折射率1.586)为成膜树脂,利用超支化聚合物分子结构疏松、便于小分子在其间扩散的特性,同时以低折射率的单官能团含氟丙烯酸酯(折射率1.372)和高活性的双官能团丙烯酸酯(折射率1.457)为记录单体制备了光致聚合物全息膜,以衍射效率为指标优化单体构成和全息膜的厚度,研究了该全息膜的衍射效率、空间分辨率、折射率调制度等性能.该光致聚合物全息材料的折射率调制度为4.82×10-3,衍射效率达到99.4%,在空间分辨率3750 lp/mm的衍射效率仍然达到85.6%,感光灵敏度56 mJ/cm2.  相似文献   

16.
Abstract

Copolymers of p-nitrobenzyl acrylate and methyl acrylate with different feed ratios are synthesized in ethyl methyl ketone using benzoyl peroxide as a free radical initiator at 70 ± 1°C. The copolymers were characterized by IR and 1H-NMR spectroscopic techniques. Copolymer compositions were determined by 1H-NMR analysis of the polymers. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman–Ross and Kelen–Tüdös. Gel permeation chromatography was used for determining the molecular weights M n and M w, and the polydispersity index. The intrinsic viscosities and the thermal properties of the homo- and copolymers are also discussed.  相似文献   

17.
本文利用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)对多壁碳纳米管(MWNTs)进行修饰使其表面接枝上烯丙基官能团,与丙烯酸酯类单体进行原位聚合,制备了一种耐高温丙烯酸酯压敏胶(PSA)。 通过傅里叶变换红外光谱仪(FT-IR)、热重分析仪(TGA)和扫描电子显微镜(SEM)表征了MWNTs和丙烯酸酯PSA的结构与性能,探讨了改性MWNTs的质量分数对PSA耐热性能和粘接性能的影响。 结果表明,与未改性的丙烯酸酯PSA相比,当改性MWNTs的质量分数为1.5%时,改性丙烯酸酯PSA的耐热性能和粘接性能最佳,热分解温度从360 ℃提高到了382 ℃,耐热温度从80 ℃提高到了155 ℃,初粘力、持粘力和180°剥离强度分别从2 h和13.66 N/(25 mm)(12号小球)提高到了27 h和17.34 N/(25 mm)(17号小球)。  相似文献   

18.
自交联型丙烯酸酯共聚物乳液的研究   总被引:7,自引:0,他引:7  
以羟甲基丙烯酰胺、丙烯酸作为活性单体,采用种子乳液聚合法制得四元体系自交联型丙烯酸酯共聚物乳液。用透射电镜观察了乳胶粒的微观形态,并对共聚物乳液的流变性,稳定性等进行了测试,考察了羟甲基丙烯酰胺和丙烯酸的含量、聚合方式对共聚物乳液性能的影响。  相似文献   

19.
两亲性丙烯酸酯共聚物的聚合研究   总被引:1,自引:0,他引:1  
刘莉  张文传 《合成化学》1998,6(4):365-371
利用过氧化苯甲酰为引发剂探讨了甲基丙烯酸β-羟乙酯和丙烯酸长链烷基酯的自由基共聚合。重点讨论了合成条件如溶剂、沉淀剂、引发剂用量、单体配比、反应时间等对共聚反应的影响以及各种聚合条件对该共聚物的组成、结构和性能的影响。并用IR,GPC,^13CNMR等手段对共聚物进行了表征。  相似文献   

20.
β-Picolinium-p-chlorophenacylide initiates radical polymerization of methyl acrylate (MA) up to 19.5% conversion without gelation due to autoacceleration. The average rate of polymerization (Rp) increases as [ylide] is raised from 1.02 to 3.06 mmol/L, the order of reaction being 0.5 ± 0.02. However, at higher concentrations (>3.06 mmol/L), Rp decreases. The monomer exponent is 1.40 when benzene is used as diluent. The overall energy of activation is computed to be 28.8 kJ/mol. A polar solvent like dimethyl-sulfoxide and a radical scavenger like hydroquinone retard the reaction. The kinetic data and ESR studies indicate that the polymerization proceeds via a free-radical mechanism. Chain termination by degradative chain (initiator) transfer appears to be significant.  相似文献   

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