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1.
在氯丁橡胶(CR)和甲基丙烯酸甲酯(MMA)接枝胶中,通过加入第二单体丙烯酸(AA),进一步提高CR/MMA接枝胶的粘接性能。研究了反应温度、反应时间、引发剂的用量及第一单体MMA的用量对接枝共聚反应的影响,确定了最佳的反应条件和配方组成。  相似文献   

2.
MMA含量对PUA复合乳液性能的影响研究   总被引:1,自引:0,他引:1  
张辉  沈慧芳  陈焕钦 《粘接》2005,26(3):21-23
以甲苯二异氰酸酯(TDI-80),聚醚二元醇(N210),二羟甲基丙酸(DMPA)和甲基丙烯酸甲酯(MMA)为主要原料,采用原位乳液聚合法,合成聚氨酯-丙烯酸酯(PUA)复合乳液,在保证二羟甲基丙酸(DMPA)含量、中和度等不变的情况下,研究了MMA含量对乳液的性能及外观的影响。结果表明,MMA对乳液外观、贮存稳定性、力学性能、吸水性等均有重要影响。MMA最佳含量为20%~30%。  相似文献   

3.
海外传真     
丙烯酸树脂回收新方法日本三菱人造丝公司在富山建设一套回收再生装置,回收能力为2000吨/年。丙烯酸树脂具有透明性的特点,在广告牌等方面有广泛应用。该公司是MMA树脂的最大生产公司,有6万吨/年成型材、片材能力,但生产过程中的边角废料过去作为产业废弃物处理。该公司采用干馏法热分解MMA树脂,将质量差、难于在工业上再利用的MMA单体精制成高纯度单体,而且MMA回收率高达90%。回收单体MMA可作为树脂原料重新用作丙烯酸树脂的制造,而且回收后的残余馏分可用作加热燃料而不需再用重油等其他燃料,降低了MMA的回收成本。该…  相似文献   

4.
据预测,未来几年世界甲基丙烯酸甲酯(MMA)需求将以7%的年增幅继续增长,到2008年亚洲地区MMA需求将达到144万吨,去年则为110万吨。需求增长主要来自于聚甲基丙烯酸甲酯(PMMA)、苯乙烯一丙烯酸甲酯、甲基丙烯酸甲酯-丁二烯-苯乙烯、人造大理石、涂料油漆、粘合剂以及铸造板材等领域。其中聚甲基丙烯酸甲酯约占MMA总需求的50%,其需求年增幅将高于7%,给MMA扩大的产能提供了更大的消化空间。  相似文献   

5.
采用挤出法以MMA/S对超细PVC单丝进行了刚性增韧。研究表明:采用MMA/S可以明显提高PVC单丝韧性,同时还可以改善加工流动性,MMA/S的加入量以3~4份为佳(以100份PVC为基准),但单丝的拉伸强度将随MMA/S添加量的增加而有所下降。  相似文献   

6.
Foster Wheeler公司中标,成为璐彩特(Lucite)国际公司新加坡甲基丙烯酸甲酯(MMA)项目的承包商。这套12万t/a的MMA装置将首次采用璐彩特专有的Alpha技术,计划2008年建成。Alpha技术以乙烯、甲醇和一氧化碳为原料生产MMA。璐彩特最近在上海漕泾投产一套10万t/a的MMA装置,采用了该公司常规的丙酮氰醇技术。  相似文献   

7.
曹辉  何虹  许谨 《浙江化工》2002,33(2):55-56
讨论了三种混合型低毒溶剂(MXA、MXB、MXC)中,各种工艺条件对接枝率的影响,CR与MMA、BA、MEA都能进行接枝反应,且后二者接枝率MMA高。  相似文献   

8.
介绍了目前甲基丙烯酸甲酯(MMA)的生产情况及用途,对MMA的未来发展作了预测。  相似文献   

9.
在传统的丙烯腈-丁二烯-苯乙烯共聚物(ABS)乳液接枝聚合中加入甲基丙烯酸甲酯(MMA),制得了改性ABS,然后与聚碳酸酯(PC)共混挤出,制得了PC/改性ABS复合材料。研究了MMA用量对PC/改性ABS复合材料的熔体流动速率(MFR)、维卡软化温度、力学性能的影响。结果表明:随着MMA用量的增加,PC/改性ABS复合材料的MFR、拉伸强度、弯曲强度和缺口冲击强度均先升高后降低。当MMA质量分数为20%时,PC/改性ABS复合材料的拉伸强度和弯曲强度均达到最大,分别为48.9 MPa和63.2 MPa;当MMA质量分数为30%时,PC/改性ABS复合材料的缺口冲击强度为41.0 kJ/m2;当MMA质量分数不高于30%时,与PC/ABS复合材料相比,PC/改性ABS复合材料的维卡软化温度更高。  相似文献   

10.
朱怀刚  李明阳 《广东化工》2012,39(17):70-71,73
文章综述了MMA防水涂料、MMA彩色防滑路面、MMA地坪涂料和MMA混凝土修复材料等系列产品的研究进展情况。  相似文献   

11.
纳米SiO_2/MMA无皂乳液聚合研究及其应用   总被引:4,自引:1,他引:4  
以纳米 Si O2 为核 ,以 MMA为壳层单体 ,进行了无皂乳液聚合。研究了单体加入方式、引发剂用量、聚合反应温度等对无皂乳液聚合的影响。核壳产物对 PVC材料的力学性能有明显的提高。  相似文献   

12.
甲基丙烯酸甲酯单体及其聚合物的新发展   总被引:2,自引:0,他引:2  
介绍目前国内外甲基丙烯酸甲酯(MMA)单体及其均聚物(PMMA)的发展概况,其中包括MMA单体的应用分配和合成路线及未来的发展趋势;MMA均聚物聚合方法、产品(成型品和板材)及其发展;加工技术开发和产品应用开发;及利用MMA单体进行接枝共聚,合成具有多功能、高性能和有附加价值的新型聚合物和改性材料。  相似文献   

13.
Nowadays,the efficient and cleaner utilization of coal have attracted wide attention due to the rich coal and rare oil/gas resources structure in China.Coal chemical looping gasification (CCLG) is a promising coal utilization technology to achieve energy conservation and emission reduction targets for highly pure synthesis gas.As a downstream product of synthesis gas,methyl methacrylate (MMA),is widely used as raw material for synthesizing polymethyl methacrylate and resin products with excellent properties.So this paper proposes a novel system integrating MMA production and CCLG (CCLG-MMA) processes aim-ing at "energy saving and low emission",in which the synthesis gas produced by CCLG and purified by dry methane reforming (DMR) reaction and Rectisol process reacts with ethylene for synthesizing MMA.Firstly,the reaction mechanism of CCLG is investigated by using Reactive force field (ReaxFF)MD simulation based on atomic models of char and oxygen carrier (Fe2O3) for obtaining optimum reac-tion temperature of fuel reactor (FR).Secondly,the steady-state simulation of CCLG-MMA system is car-ried out to verify the feasibility of MMA production.The amount of CO2 emitted by CCLG process and DMR reaction is 0.0028 (kg CO2)-1·(kg MMA)-1.The total energy consumption of the CCLG-MMA system is 45521 kJ·(kg MMA)-1,among which the consumption of MMA production part is 25293 kJ·(kg MMA)-1.The results show that the CCLG-MMA system meets CO2 emission standard and has lower energy con-sumption compared to conventional MMA production process.Finally,one control scheme is designed to verify the stability of CCLG-MMA system.The CCLG-MMA integration strategy aims to obtain highly pure MMA from multi-scale simulation perspectives,so this is an optimal design regarding all factors influencing cleaner MMA production.  相似文献   

14.
甲基丙烯酸甲酯的生产与市场   总被引:3,自引:0,他引:3  
甲基丙烯酸甲酯(MMA)的生产方法有5种,其中异丁烯氧化法被认为是最具竞争力的工艺之一。国外MMA的生产主要集中在欧、美、日。英国ICI是世界上最大的MMA生产商,其总的生产能力占世界总能力的22%,美国Rohm&Hass是世界上第二大MMA生产商。国内MMA的主要生产厂家是黑龙江龙新化工有限公司和抚顺有机玻璃厂,但生产规模均较小,1998年国内MMA的生产能力为6万t/a。由于MMA是高技术资本密集型产品,而国内由于技术、原材料、规模等原因使得产品成本非常高,严重影响市场开拓,同时大量的国外产品不断向我国倾销,严重冲击了国内MMA的生产,迫使许多厂家停产。预计在未来MMA将具有广泛的应用前景,因此,利用异丁烯氧化技术引进或合资建成1—2套具有经济规模的MMA装置很有发展前途。  相似文献   

15.
The effects of maleic acid and styrene on the polymerization of methyl methacrylate (MMA) have been studied. Both comonomers play a considerable role in terms of particle size and MMA conversion. The polymerization of MMA in the presence of maleic acid can result in larger particles and a higher MMA conversion. However, in the presence of styrene, the polymerization process yields smaller particles and low MMA conversion. This can be related to the different properties of maleic acid and styrene. Maleic acid, a hydrophilic and electron‐withdrawing comonomer, can play a positive role in stabilizing the particles and increasing MMA activation. However, for styrene, these effects are reversed due to its opposite properties. The change in particle size may be caused by the change in particle stabilization. The change of MMA conversion can be kinetically attributed to the effects of maleic acid and styrene on the activation process. Copyright © 2004 Society of Chemical Industry  相似文献   

16.
Iñigo González 《Polymer》2007,48(9):2542-2547
The effect of the monomer ratio on the microstructure of BA/MMA emulsion copolymers was investigated. Monomer ratios spanned from pure BA used for adhesives to 50/50 wt/wt BA/MMA copolymers used for coatings. The gel content varied from 55% for pure BA to nil for the 50/50 copolymer. The branching level was reduced from 2.6% for pure BA to 0.3% for a 75/25 BA/MMA copolymer. The mechanisms responsible for the reduction of gel content can be found in the lower reactivity of the MMA terminated chains for hydrogen abstraction, the absence of abstractable hydrogens in the MMA units and the fact that MMA radicals terminate predominantly by disproportionation. The reduction of the level of branches is mainly due to the lower reactivity of MMA for intramolecular transfer and the lower instantaneous conversions that favored propagation over backbiting.  相似文献   

17.
The crosslinked polymeric microspheres (GMA/MMA) of glycyl methacrylate (GMA) and methyl methacrylate (MMA) were prepared by suspension polymerization. Polyethylene glycol (PEG) was grafted on GMA/MMA microsphers via the ring‐opening reaction of the epoxy groups on the surfaces of GMA/MMA microspheres, forming a polymer‐supported triphase catalyst, PEG‐GMA/MMA. The Phase‐transfer catalytic activity of PEG‐GMA/MMA microspheres was evaluated using the esterification reaction of n‐chlorobutane in organic phase and benzoic acid in water phase as a model system. The effects of various factors on the phase transfer catalysis reaction of liquid–solid–liquid were investigated. The experimental results show that the PEG‐GMA/MMA microspheres are an effective and stable triphase catalyst for the esterification reaction carried out between oil phase and water phase. The polarity of the organic solvent, the ratio of oil phase volume to water phase volume and the density of the grafted PEG on PEG‐GMA/MMA microspheres affect the reaction rate greatly. For this investigated system, the solvent with high polarity is appropriate, an adequate volume ratio of oil phase to water phase is 2:1, and the optimal PEG density on the polymeric microspheres is 15 g/100 g. Triphase catalysts offer many advantages associated with heterogeneous catalysts such as easy separation from the reaction mixture and reusability. The activity of PEG‐GMA/MMA microspheres is not nearly decreased after reusing of 10 recycles. © 2009 American Institute of Chemical Engineers AIChE J, 2010  相似文献   

18.
In this work the well-defined fluorinated acrylic copolymer latex and solution were prepared by the radical initiated seed emulsion polymerization and solution polymerization, respectively, using the same monomers of dodecafluoroheptyl methacrylate (DFHM), butyl acrylate (BA) and methyl methylacrylate (MMA). The copolymer latex BA/MMA/DFHM was designed as core–shell structure and the copolymer solution poly(BA–MMA–DFHM) was structured with low molecular weight. The chemical and morphology structures as well as the film properties obtained from latex and solution were analyzed and compared by spectroscopic techniques (FT-IR and NMR), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), scanning electron microscopy coupled with energy-dispersive X-ray detector (SEM–EDX) and static contact angles (CAs) instrument. Moreover, the BA/MMA/DFHM latex and poly(BA–MMA–DFHM) solution (with 29 wt% of DFHM) were applied onto two kinds of sandstone samples by capillary absorption, and their preliminary protecting efficiency was evaluated. It is demonstrated that the comprehensive performances of BA/MMA/DFHM latex films were quite comparable to those of poly(BA–MMA–DFHM) solution cast films, the latter exhibited a better protective performance.  相似文献   

19.
Conductive polymer particles, polyaniline (PANI)‐coated poly(methyl methacrylate–butyl acrylate–acrylic acid) [P(MMA–BA–AA)] nanoparticles, were prepared. The P(MMA–BA–AA)/PANI core–shell complex particles were synthesized with a two‐step miniemulsion polymerization method with P(MMA–BA–AA) as the core and PANI as the shell. The first step was to prepare the P(MMA–BA–AA) latex particles as the core via miniemulsion polymerization and then to prepare the P(MMA–BA–AA)/PANI core–shell particles. The aniline monomer was added to the mixture of water and core nanoparticles. The aniline monomer could be attracted near the outer surface of the core particles. The polymerization of aniline was started under the action of ammonium persulfate (APS). The final product was the desired core–shell nanoparticles. The morphology of the P(MMA–BA–AA) and P(MMA–BA–AA)/PANI particles was characterized with transmission electron microscopy. The core–shell structure of the P(MMA–BA–AA)/PANI composites was further determined by Fourier transform spectroscopy and ultraviolet–visible measurements. The conductive flakes made from the core–shell latexes were prepared, and the electrical conductivities of the flakes were studied. The highest conductivity of the P(MMA–BA–AA)/PANI pellets was 2.05 S/cm. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

20.
The epoxy‐group‐containing microspheres from cross‐linked glycidyl methacrylate and methyl methacrylate, poly(GMA–MMA), were prepared by suspension polymerisation. The epoxy groups of the poly(GMA–MMA) microspheres were used for grafting with an anionic polymer polyethylenimine (PEI) to prepare non‐specific affinity adsorbents (poly(GMA–MMA)–PEI) for bilirubin removal. The specificity of the poly(GMA–MMA)–PEI adsorbent to bilirubin was further increased by immobilization of human serum albumin (HSA) via adsorption onto PEI‐grafted poly(GMA–MMA) adsorbent. Various amounts of HSA were immobilized on the poly(GMA–MMA)–PEI adsorbent by changing the medium pH and initial HSA concentration. The maximum HSA content was obtained at 68.3 mg g?1 microspheres. The effects of pH, ionic strength, temperature and initial bilirubin concentration on the adsorption capacity of both adsorbents were investigated in a batch system. Separation of bilirubin from human serum was also investigated in a continuous‐flow system. The bilirubin adsorption on the poly(GMA–MMA)–PEI and poly(GMA–MMA)–PEI–HSA was not well described by the Langmuir model, but obeyed the Freundlich isotherm model. The poly(GMA–MMA)–PEI affinity microspheres are stable when subjected to sanitization with sodium hydroxide after repeated adsorption–desorption cycles. Copyright © 2004 Society of Chemical Industry  相似文献   

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