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1.
根据氯乙烯(VC)/N-苯基马来酰亚胺(PMI)/乙烯基单体悬浮共聚合工艺的特点,确定了倒加料的聚合工艺,比较了丙烯腈(AN),甲基丙烯酸甲酯(MMA)对VC/PMI聚合速率的影响,研究了AN的用量和聚合温度对VC/PMI/AN三元悬浮共聚合速率的影响。  相似文献   

2.
3.
Acrylonitrile‐co‐styrene‐co‐methylmethacrylate (AN‐S‐MMA) terpolymer was prepared by bulk and emulsifier‐free emulsion polymerization techniques. The bulk and emulsion terpolymers were characterized by means of Fourierr transform infrared spectroscopy, 13C nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography, thermal gravimetric analysis, and elemental analysis. The kinetics of the terpolymerization were studied. The terpolymers were then incorporated into butadiene—acrylonitrile rubber (NBR)/ethylene propylene diene monomer rubber (EPDM) blends and into chloroprene rubber (CR)/EPDM blend. The terpolymers were then tested for potential as compatibilizers by using scanning electron microscopy and differential scanning calorimetry. The terpolymers improved the compatibility of CR/EPDM and NBR/EPDM blends. The physicomechanical properties of CR/EPDM and NBR/EPDM blend vulcanizates revealed that the incorporation of terpolymers was advantageous, since they resulted in blend vulcanizates with higher 100% moduli and with more thermally stable mechanical properties than the individual rubbers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3143–3153, 2003  相似文献   

4.
Different types of the styrene ? methyl methacrylate ?acrylonitrile terpolymers were synthesized according to the recently proposed concept of the living nitroxide-mediated terpolymerization. Random azeotropic and gradient terpolymers were prepared using the living TEMPO-mediated polymerization. Block random terpolymer was obtained via the living terpolymerization initiated by macro-alkoxyamine polystyrene-SG1. In all systems, terpolymerization proceeds in the living manner even in the presence of TEMPO. Upon complete polymerization at high conversions of monomers, the molecular weight of terpolymers linearly increases with the monomer conversion. The resultant terpolymers were characterized by the methods of turbidimetric titration, GPC, DSC, and TGA, and their characteristics were compared with their non-living analogs synthesized by the conventional radical polymerization. The effect of the macromolecular structure on the thermal stability of the terpolymers was studied.  相似文献   

5.
苯乙烯-异戊二烯-丁二烯三元乳液共聚合反应研究   总被引:1,自引:0,他引:1  
以去离子水为分散介质、歧化松香酸钾和脂肪酸钠为乳化剂、十二硫醇为链转移剂、磷酸钠为电解质、过硫酸钾为引发剂,在50℃下,通过乳液聚合的方法合成了苯乙烯、异戊二烯、丁二烯三元共聚物(ESIBR)。考察了聚合温度、引发剂、链转移剂、电解质用量对三元乳液共聚合速率的影响,通过红外光谱仪(FTIR)与核磁共振(1H-NMR)对三元共聚物的组成及微观结构进行了分析表征。结果表明,随着聚合温度的升高,聚合速率显著加快,反应诱导期缩短;随着引发剂用量的增加,聚合反应速率增大;在实验范围内,链转移剂与电解质用量对共聚反应速率无明显影响。单体质量配比为S/I/B=28/36/36时,转化率在70%以内,共聚物中结合苯乙烯含量随着转化率的提高而增加,结合苯乙烯质量分数由20%增至26%;结合异戊二烯量随转化率的提高而降低,结合异戊二烯质量分数由47%降至41%;而结合丁二烯量却无明显变化,其质量分数基本都在33%左右。  相似文献   

6.
As to control the increased rate of environmental pollution there is an urgent need to develop improved biodegradable materials regarding the old polymeric packaging materials. It has been done by the incorporation of carbon nanomaterials to the biodegradable starch terpolymers of acrylic acid, methyl methacrylate (MMA), acrylonitrile (AN), 2-Ethylhexyl acrylate (2-EHA), and Ethyl acrylate (EA). The starch-terpolymers were prepared through the free radical polymerization technique using AA, MMA, AN, 2-EHA, EA as monomers. Two different starch-terpolymers were further mixed with carbon nanoparticles (NPs) to form a biodegradable nanocomposite. The biodegradable starch-grafted terpolymers-carbon nanocomposites (STPC NCs) were characterized through scanning electron microscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimeter, and UV–Visible spectrophotometry. Further, resistivity, electrical conductivity, and biodegradability tests were performed to check its properties for packing materials. The biodegradation of SGCP-composites recorded using the soil burial method was up to 78%. Starch-terpolymers were prepared via free-radical polymerization The biodegradation capability of starch-grafted terpolymers was found to be 78% The decrease in water vapor permeability and solubility proves their utilization as food packaging material  相似文献   

7.
2-Pyrimidyl acrylamide monomer (2PA) has been prepared by the reaction of 2-amino pyrimidine with acrylolyl chloride in the presence of triethylamine as catalyst. Its structure was confirmed by IR and 1H NMR spectroscopy. Ternary copolymerizations of 2-pyrimidyl acrylamide monomer (2PA) with methyl acrylate (MA), methyl methacrylate (MMA), ethyl acrylate (EA), butyl acrylate (BuA) and acrylonitrile (AN) were carried out in THF at 65°C in the presence of a free radical initiator. Experimental terpolymerization data agree well with calculations based on the Alfrey–Goldfinger equation. The determination of unitary, binary and ternary azeotropies of the various systems studied were easily handled by a computer. The ternary azeotropic compositions for 2PA–MA–AN and 2PA–MMA–AN were 32.20:17.5:50.30 and 13.54:52.64:33.82mol%, respectively. Pseudo-azeotropic regions were identified where the deviation between feed and polymer composition is very small.  相似文献   

8.
(Ind)2ZrCl2 catalyst was synthesized and used for copolymerization of ethylene and propylene (EPR) and terpolymerization of ethylene propylene and 5‐ethyldiene‐2‐norbornene (ENB). Methylaluminoxane (MAO) was used as cocatalyst. The activity of the catalyst was higher in copolymerization of ethylene and propylene (EPR) rather than in terpolymerization of ethylene, propylene and diene monomers. The effects of [Al] : [Zr] molar ratio, polymerization temperature, pressure ratio of ethylene/propylene and the ENB concentration on the terpolymerization behavior were studied. The highest productivity of the catalyst was obtained at 60°C, [Al] : [Zr] molar ratios of 750 : 1 and 500 : 1 for copolymerization and terpolymerization, respectively. Increasing the molar ratio of [Al] : [Zr] up to 500 : 1 increased the ethylene and ENB contents of the terpolymers, while beyond this ratio the productivity of the catalyst dropped, leading to lower ethylene and ENB contents. Terpolymerization was carried out batchwise at temperatures from 40 to 70°C. Rate time profiles of the polymerization were a decay type for both copolymerization and terpolymerization. Glass transition temperatures (Tg) of the obtained terpolymers were between ?64 and ?52°C. Glass transition temperatures of both copolymers and terpolymers were decreased with increased ethylene content of the polymers. Dynamic mechanical and rheological properties of the obtained polymers were studied. A compounded EPDM showed good thermal stability with time. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

9.
偏氯乙烯/丙烯腈/苯乙烯悬浮共聚合动力学   总被引:1,自引:0,他引:1  
本文研究了偏氯乙烯(VDC)/丙烯腈(AN)/苯乙烯(St)三元悬浮共聚合体系的聚合机理、共聚速率、非聚物组成及其特性粘度的影响因素。实验表明随着投料配比的改变,可分成四个不同聚合机理区域。St对VDC/AN/St三元悬浮共聚有缓聚作用。VDC三元悬浮共聚速率可用半经验模型,dC/dt=αC^β「Ⅰ」o^γexp(-γkdt)描述,由实验得到模型参数γ值为2.24,模型参数α、β是聚合温度与引发剂浓度的函数。VDC-AN-St三元悬浮共聚物存在着较宽的VDC组成分布,并受到单体AN水溶性的影响,经AN动态相平衡校正后,可预测VDC三元共聚物组成。VDC-AN-St共聚物的特性粘度随着转化率的升高而增大。在相同引发剂用量下,高转化率VDC-AN-St共聚物特性粘度的对数与温度的倒数成线性关系。  相似文献   

10.
Three random and three block copolymers of methyl methacrylate (MMA) and octadecyl acrylate (ODA) were synthesized by atom transfer radical polymerization. These copolymers were assessed for their application as stabilizers in the one-step non-aqueous dispersion (NAD) polymerization of MMA and of acrylonitrile (AN) in a non-polar solvent mixture of hexane and dodecane. In all cases stable spherical micro-particle colloidal dispersions were formed with particle diameters in the range of 62-2725 nm for PMMA. Uniform monodisperse PMMA particles with standard deviations in size distributions of less than 5% were obtained in two cases demonstrating the utility of ODA:MMA copolymers as replacement preformed stabilizers in the one-step synthesis of MMA micro-spheres. Overall the block copolymer PMMA64-block-PODA36 gave greater control over size when varying the solvent:monomer ration than a related gradient PMMA-PODA copolymer. These copolymers were further used as stabilizers in the one-step NAD polymerization of MMA with ethylene glycol dimethacrylate (EGDMA) under similar conditions allowing for the preparation of monodisperse cross-linked PMMA particles with diameters ranging from 110 to 1700 nm. The general utility of the copolymers as stabilizers was demonstrated by the NAD polymerization of acrylonitrile (AN) in non-polar solvent mixture of hexane and dodecane giving ‘crumpled’ latex dispersions with particle diameters in the range 85-483 nm.  相似文献   

11.
Low conversion kinetics of terpolymerization of N,N‐dimethylaminoethyl methacrylate (DMAEM) and dodecyl methacrylate (DDMA) with methyl methacrylate (MMA) or styrene (ST) was investigated. Reactions were performed at 70°C, in toluene solutions, using peroxide initiator. The interdependence between terpolymer and monomer feed composition was successfully described by Alfrey‐Goldfinger equation and the unitary, binary, and ternary azeotropes were calculated. In MMA‐containing system, the wide pseudoazeotropic region with existence of true azeotropic point was observed and experimentally confirmed at the DMAEM:MMA:DDMA molar ratio of 56:41:3. In the ST‐containing system compositional heterogeneity was significant, more than 10 mol%. Required copolymerization reactivity ratios were determined by linear and nonlinear methods. The glass transition temperatures of synthesized terpolymers are found to be between those of the corresponding homopolymers and relative to their content. Increase in the MMA or ST contents and decrease in the DDMA content in terpolymers results in an increase in their glass transition temperatures. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers  相似文献   

12.
Terpolymers of acrylonitrile (AN), vinyl acetate (VA) (7.5–30 mol-%, related to AN), and divinylbenzene (DVB) (10 wt.-%) were prepared by suspension polymerization. The diluents used were mixtures of toluene or cyclohexanol (90 vol.-%) with solvents (10 vol.-%) such as hexadecane (HD), octane (O), dodecane (D), 2-ethylhexanol (E) or benzyl alcohol (B). It has been found that AN-VA-DVB terpolymers have a higher porosity, about 0.61–0.68, than corresponding AN-DVB copolymers. The terpolymers obtained with mixtures of various diluents differ in their supermolecular structure although they had similar porosity characteristics. The thermal effects accompanying heating of the terpolymers above 200°C significantly exceed that of nitrile groups cyclization observed of the other AN polymers.  相似文献   

13.
In this study, spruce samples were impregnated with acrylonitrile (AN), methyl methacrylate (MMA), allyl glycidyl ether (AGE), AGE/AN or AGE/MMA monomers and monomer mixtures. In situ polymerization (copolymerization) was achieved by gamma irradiation. The relationship between the mechanical properties of the wood‐polymer(copolymer) composites and the kind and quantity of polymers and copolymers, irradiation dose and artificial aging treatment of the wood was investigated. The fine structure of wood‐polymer(copolymer) composites was determined by Scanning Electron Microscopy. The presence of homopolymer and copolymers increased the mechanical properties of the wood. The compressive strength and Brinell Hardness Numbers, determined for untreated and treated wood samples, indicated that the mechanical strength of wood‐polymer (copolyrner) was significantly increased in the presence of P(AGE/MMA). At maximum percent conversion, the percentage increase in the compressive strength with regard to the applied force perpendicular to the fibers in spruce was 218%. After aging for 28 days, it was found that there were no significant changes in mechanical stability.  相似文献   

14.
To develop polymer systems with improved lithographic resist properties, terpolymers of methyl methacrylate/methacrylonitrile/methyl α-chloroacryate (MMA/MCN/MCA), methyl methacrylate/methacrylonitrile/α-chloroacrylonitrile (MMA/MCN/ACAN), and methyl methacrylate/methacrylonitrile/vinylidene chloride (MMA/MCN/VDC) were prepared by emulsion polymerization. Also one methyl methacrylate/ methyl α-chloroacylate/α-chloroacrylonitrile (MMA/MCA/ ACAN) terpolymer was prepared. The radiation susceptibilities of these terpolymers were measured using the 60Coγ-irradiation method. Molecular weights were determined both by membrane osmometry and gel permeation chromatography. All terpolymers exhibited higher radiation-degradation susceptibilities than poly(methyl methacrylate). The Gs values did not follow the general trend, previously observed with MCN/MCA copolymers, of being directly proportional to the respective terpolymer compositions. In some cases, the addition of small quantities of α-chlorine-containing monomers caused Gx to increase. This observation greatly differs from those observed for copolymer systems such as MMA/MCA, MCN/MCA, MMA/ ACAN, etc. studied previously. Terpolymerization gives highly soluble polymers especially suitable for wet development by many solvents. This is an important consideration for polymers with high mole fractions of methacrylonitrile (MCN) or vinylidene chloride (VDC) which are rendered soluble in development solvents. The electron-beam sensitivities were obtained for samples of three classes of the terpolymers and they were higher than that of PMMA. For example, at 20Kev a 62/34/4 MMA/MCN/MCA terpolymer exhibited a sensitivity of 1.3 × 10?5 coulombs cm?2 at l/lo = 1. The introduction of ACAN narrows the working range for positive resist behavior. For example MMA/MCN/ACAN(41/40/19) has a sensitivity of 8.3 × 10?6 coulombs cm?2 at l/l0 = 0.6 but it crosslinks at 1 ? 1.3 × 10? coulombs cm2. The MMA/MCN/VDC(21/76/3) polymer was about 25 times more sensitive than PMMA (7 × 10?6 C cm?2 at l/l0=1).  相似文献   

15.
This study investigated the possibility of using styrene, a weak donor forming donor(D)/acceptor(A) pairs with electron‐poor (EP) vinyl monomers, for initiating spontaneous photopolymerization and photografting of the copolymers onto polypropylene. Maleic anhydride (MA), methyl methacrylate (MMA), methyl acrylate (MAC), dimethyl maleate (DMMA), acrylonitrile (AN) and acrylic acid (AA) were the EP monomers used. Grafting yields together with FTIR analyses were used to confirm the presence of grafting. Styrene/MMA and styrene/AN systems achieved significant grafting, but such levels of grafting were not observed in the styrene/MAC and styrene/DMMA systems. No grafting was observed for styrene/AA or styrene/MA systems, but the latter system underwent photopolymerization. The effect of solvents on grafting was evaluated on styrene/MMA and styrene/AN systems and dimethylformamide (DMF) was found to retard grafting of both D/A systems. In contrast, chloroform and methanol enhanced grafting of the styrene/AN system although these two solvents had no significant effect on the grafting of the styrene/MMA system. Copyright © 2004 Society of Chemical Industry  相似文献   

16.
Acrylonitrile (AN), methyl methacrylate (MMA), allyl glycidyl ether (AGE), AGE + AN monomer, AGE + MMA monomer, and monomer mixtures were used to conserve and consolidate beechwood. After the impregnation of these monomer mixtures in the wood, polymerization was accomplished by gamma irradiation. The fine structures of wood + polymer(copolymer) composites were investigated by scanning electron microscopy (SEM). The copolymer obtained from AGE + MMA monomer mixtures showed the optimum compatibility with the wood. The compressive strength and Brinell hardness numbers determined for untreated and treated wood samples indicated that the mechanical strength was greater in wood + polymer(copolymer) composites than in untreated wood and was greatest in the samples containing AGE + AN and AGE + MMA copolymers. All monomer couples used in this study increased the mechanical strength of the wood and protected the samples against aging. AGE + MMA copolymers were the most effective in protecting the wood against various environmental attacks. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1515–1523, 1999  相似文献   

17.
从氯乙烯/N-苯基马来酰亚胺/丙烯腈三元悬浮共聚的技术特点出发,研究了加料方式对聚合工艺及产物颗粒特性的影响,并在此基础上考察了引发剂体系的影响,确定了适宜的引发剂种类及用量。  相似文献   

18.
In this work the thermal stability of polymeric additives for the improvement of rheological behavior of mineral lubricating oils was investigated. The systems studied comprised methyl methacrylate (MMA)/dodecyl methacrylate (DDMA)/octadecyl methacrylate (ODMA) and styrene (Sty)/DDMA/ODMA terpolymers. The composition of the terpolymers was determined by the 1H nuclear magnetic resonance spectroscopy and molar mass distribution by the size exclusion chromatography. The thermal degradation of terpolymers was studied by the thermogravimetric analysis. Sty/DDMA/ODMA terpolymers exhibited an improved thermal stability in comparison with MMA/DDMA/ODMA terpolymers of the corresponding compositions. Thus, the temperatures of 50% weight loss were found to be 313°C and 363°C for MMA terpolymer and Sty terpolymer, respectively, where x (MMA) = x (Sty) = 30 mol%.  相似文献   

19.
Terpolymers of N‐phenylmaleimide (PMI), methyl methacrylate (MMA), and acrylonitrile (AN) were synthesized by emulsion polymerization. The thermal properties of the terpolymers, at different PMI and AN feed contents, were investigated by TBA, TGA, and the Vicat softening point test. The results show that the glass transition temperature (Tg) and decomposition temperature of the terpolymers increase with increasing PMI feed content. Furthermore, the Vicat softening points of the terpolymers increase with the PMI feed content. The M?w and M?n of the terpolymers were also determined by GPC. The results show that the M?w and M?n of the terpolymers have a maximum value in the range of 0–30% PMI feed content and decrease with an increasing AN feed content. The mechanical properties (tensile strength and impact strength) of the terpolymers decrease with an increasing PMI feed content and increase with an increasing AN feed content. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2455–2462, 2001  相似文献   

20.
Ternary copolymerizations of tri-n-butyltin 4-acryloyloxybenzoate (ABTB) with acrylonitrile (AN) and alkyl acrylates [methyl (MA), ethyl (EA) or butyl acrylate (BA)], methyl methacrylate (MMA) or styrene (ST) were carried out in solution at 70°C in the presence of free radical initiator. Experimental terpolymerization data agreed well with calculations based on the Alfrey-Goldfinger equation. The determination of unitary, binary and ternary azeotropies of various systems studied was easily handled by a computer program. The results obtained show that there is no ternary azeotropic composition for any terpolymer, system studied. Selective unitary and binary azeotropic compositions were polymerized and the results obtained show good agreement between the theoretical and experimental terpolymer composition for each case.  相似文献   

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