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马来酸酐熔融接枝氯化聚乙烯 总被引:1,自引:0,他引:1
以过氧化二异丙苯、过氧化二苯甲酰、偶氮二异丁腈为引发剂,研究了引发剂及马来酸酐用量对熔融接枝氯化聚乙烯的接枝率、硫化工艺性及力学性能的影响,并用红外光谱表征研究了接枝结构及机理。制备了马来酸酐接枝氯化聚乙烯/聚乙烯共混物,通过共混物的性能考察了马来酸酐接枝氯化聚乙烯的自黏性,并采用差示扫描量热法、热重分析法和扫描电镜对共混物进行了热行为和形态的分析。结果表明,过氧化二苯甲酰引发马来酸酐接枝氯化聚乙烯的效果较好,组分最优配伍时(过氧化二苯甲酰1.6份,马来酸酐8份)接枝物的硫化工艺性、力学性能和热性能明显改善,硫化出现了典型的平坦区,拉伸强度达到16.7 MPa。共混物的力学性能和耐热性能均有所提高,接枝后氯化聚乙烯的自黏性有较大程度的改善。 相似文献
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采用反相悬浮法制备了颗粒状接枝共聚物———氯化聚乙烯接枝丙烯酸(CPE-g-AA)、氯化聚乙烯接枝丙烯酰胺(CPE-g-AM)和氯化聚乙烯接枝混合单体丙烯酸、丙烯酰胺[CPE-g-(AA-AM)],并通过热压法制得接枝共聚物片材。考察了颗粒状接枝共聚物和接枝共聚物片材的吸水膨胀性能。结果表明,接枝共聚物的吸水性能与接枝单体的种类及其接枝率有关,相同接枝率的CPE-g-AA的吸水量比CPE-g-AM的大。当混和单体丙烯酸/丙烯酰胺的质量比为2/2时,所得接枝共聚物的抗盐性能最好。接枝共聚物片材可反复吸水膨胀,接枝率为62%的CPE-g-AA片材的二次吸水达到平衡时的吸水率和膨胀率分别为120%和41%。通过测定接枝共聚物的接触角表明,CPE-g-AA对水的润湿作用比CPE-g-AM明显。 相似文献
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氯化聚丙烯是聚丙烯的氯化改性产物,通过改性,其硬度、耐磨性、耐酸性、耐盐水性能比聚丙烯都好,耐热、耐老化性也优于聚丙烯。但其性能尤其是粘接性能还不能满足其在胶粘刺等方面的需要,为了进一步提高氯化聚丙烯的粘接性能,拓宽其应用领域,需对氯化聚丙烯改性。接枝共聚法是一种很好的化学改性方法。本文以丙烯酸(AA)作为接枝单体,以过氧化苯甲酰(BPO)为引发剂,以甲苯为溶刺,采用液相接枝共聚法,将丙烯酸单体接枝到氯化聚丙烯大分子链上,得到丙烯酸改性氯化聚丙烯产物。系统研究了反应温度、反应时间、引发剂过氧化苯甲酰用量和丙烯酸单体用量等因素对丙烯酸接枝改性的氯化聚丙烯产物粘接性能的影响,得出了较佳的工艺条件是反应温度T=100℃,反应时间t=3.5h,原料质量配比为100份氯化聚丙烯、3份丙烯酸和0.3份的过氧化二苯甲酰。研究还表明,丙烯酸改性的氯化聚丙烯的粘接性能优于氯化聚丙烯的粘接性能。 相似文献
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PE氯化原位接枝丙烯酸-2-羟基乙酯(CPE-cg-HEA)及丙烯酸丁酯(CPE-cg-BA)均具有优良综合物理力学性能。本文主要讨论CPE-cg-HEA及CPE-cg-BA工业化制备过程。在2m3搅拌反应釜中进行固相氯化原位接枝反应,在PE氯化同时进行接枝反应,最终将丙烯酸-2-羟乙酯及丙烯酸丁酯(HEA、BA)分别接枝到骨架聚合物氯化聚乙烯(CPE)上。对产物物理力学性能进行了测试,并分别与实验室制备的接枝物和商品CPE性能进行了比较。实验结果表明了接枝共聚物工业化的可行性,与CPE相比具有更好的综合性能。 相似文献
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以甲基环己烷为溶剂、过氧化二苯甲酰(BPO)为引发剂,加入马来酸酐(MAH)以及苯乙烯(St)对氯化聚丙烯(CPP)进行接枝改性。系统研究了单体MAH、St、过氧化二苯甲酰(BPO)对MAH接枝率的影响,并对其影响因素进行了分析。用红外光谱(FTIR)表征了产物结构,用滴定的方法测定了接枝率,实验结果表面:最佳反应条件为BPO/CPP投料比为10%,St/MAH投料比为1∶1,MAH/CPP投料比为20%,反应温度为100℃,反应时间为2 h。通过聚丙烯(PP)板涂装底漆附着力测试表明,当氯化聚丙烯接枝马来酸酐(CPP-g-MAH)接枝率达到3.14%时涂层附着力等级可达到0级。 相似文献
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共聚合阳离子聚丙烯酰胺的合成及性能测试 总被引:10,自引:0,他引:10
首先合成阳离子单体N—(二甲氨基)甲基丙烯酰胺,然后用共聚合法合成阳离子聚丙烯酰胺。单体合成中探讨了经甲基二甲胺的合成工艺,当n(甲醛):n(二甲胺)=2:1,反应温度为55℃,反应时间为2h时,羟甲基二甲胺的收率最高;并通过NMR确定了其结构。采用正交实验,研究了共聚合反应中n(丙烯酰胺):n(阳离子丙烯酰胺)、温度、引发剂用量对聚合反应的影响。研究结果表明,n(丙烯酰胺):n(阳离子丙烯酰胺)=10:1,温度为45℃,引发剂质量分数为0.04%时,效果最佳,达到了一定的絮凝效果。 相似文献
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悬浮溶胀法合成接枝聚丙烯 总被引:10,自引:1,他引:9
用BPO作引发剂以水相悬浮胀法合成接枝聚丙烯,研究了反应条件、组分等因素对PP的接枝率(Gr)和接枝效率(Ge)的影响,发现溶胀剂、悬浮剂、引发剂、催化剂是该接枝物的主要影响因素。用此方法接枝的聚丙烯有工艺简单,接枝率高,聚丙烯降解程度小等优点,用它作PP/CaCO3、PP/PA6、PP/MBS体系的相容剂,测试结果表明,复合材料的力学性能有很大的提高。 相似文献
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A new method of synthesizing a superabsorbent resin (SAR) from an acrylic acid/ammonium acrylate copolymer by direct UV photopolymerization was studied. The effects of the degree of neutralization of acrylic acid, the photoinitiators, the crosslinking agents, and the UV‐light exposure time on the water absorbency (Q) were investigated. The results showed that Q of an SAR based on Irgacure 1700 or Irgacure 1800 and Irgacure 651 was high, reaching about 1200 mL/g, but under the same conditions, Q was low for an SAR based on other photoinitiators. The UV absorption spectrum proved that the photoinitiators matched the UV light source. Among the crosslinking agents, N,N′‐methylene bisacrylamide was more efficient than the others at a small concentration and a high value of Q. 13C‐NMR spectrometry was used to identify the mechanism of the crosslinking reaction through the esterification of hydroxyethyl acrylate (HEA) and 2‐hydroxypropyl acrylate with carboxylic acid group in acrylic acid/ammonium acrylate copolymerization, but the efficiency of the crosslinking reaction by esterification was lower than that of the copolymerization of vinyl groups in the crosslinking agent. Q of the acrylic acid/ammonium acrylate copolymer for the SAR reached 1255 mL/g under certain conditions (degree of neutralization of acrylic acid = 75%, Irgacure 651 concentration = 0.2 wt %, [HEA] = 0.2 wt %, exposure time = 10 min). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 546–555, 2005 相似文献
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F. J. Escudero Sanz J. R. Ochoa Gómez P. M. Sasia E. Díaz de Apodaca P. Río 《应用聚合物科学杂志》2007,103(5):2826-2836
Acrylamide/2‐acryloxyethyltrimethyl ammon‐ium chloride copolymers in inverse microemulsion, with a cationic charge density of 60% and a concentration of active matter of 30 wt %, of interest as flocculants have been obtained by inverse microemulsion copolymerization. Interesting inverse microemulsion formulations from both industrial and economical standpoints were selected from pseudoternary phase diagrams. These formulations were polymerized by semicontinuous free radical copolymerization in inverse microemulsion using sodium disulfite and ammonium persulfate as initiators. Influence of initiators and initiator addition conditions (specific flow rate and concentration) on semicontinuous polymerization and final product properties as flocculants have been studied. A strong difference in copolymer solution viscosity has been found when an aqueous solution of sodium disulfite is used as initiator instead of sodium disulfite/ammonium persulfate couple redox, specially for low sodium disulfite solution feeding flow. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2826–2836, 2007 相似文献
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聚乳酸是目前最具竞争力的生物降解高分子材料,但也存在脆性过大、亲水性差、售价太高等明显缺点。本文综述了近年来以聚乳酸为主链进行的接枝聚合反应。聚乳酸接枝物的合成,能够明显改善聚乳酸的表面性能。而且可以在聚乳酸与其他高分子材料的共混体系中发挥明显的增容作用,为新型聚乳酸共混物的制备提供了可能性。 相似文献
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以诺维信435酶为催化剂,在有机溶剂DMSO中合成了羟乙基淀粉/DL-丙交酯接枝共聚物。研究了底物摩尔比、温度对接枝率的影响。发现当底物摩尔比大于6,温度为50℃时接枝率最高。利用傅立叶红外吸收光谱(FTIR)对接枝产物的结构进行表征。 相似文献
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Akihiro Tagaya Tomoaki Harada Koutarou Koike Yasuhiro Koike Yoshiyuki Okamoto Hongxiang Teng Liang Yang 《应用聚合物科学杂志》2007,106(6):4219-4224
Copolymers of methyl methacrylate (MMA) and pentafluorophenyl methacrylate (PFPMA) of various compositions were prepared with a free‐radical initiator. When PFPMA was included in the copolymers, the glass‐transition temperatures increased and showed a positive deviation from the Gordon–Taylor equation. A copolymer containing 20 wt % PFPMA exhibited almost zero orientational birefringence, and the photoelastic birefringence became zero when the copolymer contained 13 wt % PFPMA. When 20 wt % PFPMA was incorporated into the MMA copolymer, its water absorption decreased to 0.4 wt % versus 1.8 wt % for poly(methyl methacrylate) (PMMA) under the same condition. The flammability of the PFPMA/MMA copolymer was reduced in comparison with that of the MMA homopolymer. The refractive indices of the PFPMA/MMA copolymers were very close to that of PMMA, and the transmittances of the copolymers were slightly better than that of PMMA. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献