Surface Properties of the Microgels Based on N-isopropylacrylamide and Tert-butyl Acrylate by Using N,N′-methylene-bis(acrylamide) and Clay as Cross-linker

Adopting N,N′-methylene-bis(acrylamide) (MBA) and inorganic clay (hectorite) as chemical and physical cross-linking agent, respectively, a series temperature sensitive microgels, based on N-isopropylacrylamide (NIPAM) as a main monomer and tert-butyl acrylate (tBA) as a comonomer were synthesized by surfactant-free emulsion polymerization(SFEP). The microgel particle size and morphology was investigated by means of Atomic Force Microscope (AFM). The surface tension of latex particles was measured by OCA 40 Micro Video based contact angle measuring device. The results showed that the particle size of the microgels with clay as cross-linker was smaller than that using MBA as chemical cross-linker, but exterior morphology of physical microgels is not as clean and neat as chemical microgels. In general, surface tension decreases with increasing hydrophobic tBA content. These smart microgels varied with temperature have the potential applications in the field of drug delivery and intelligent gel fiber.

Heteropolyacids Catalysis in Synthesizing Butylacrylate

The catalytic activities of some heteropolyacids(HPAs) in synthesizing butyl acrylate are reported. It has been demonstrated that 12 tungstophosphoric acid is the most effective catalyst among more than 20 HPA(salts). Various factors concerned in this reaction have been investigated. The optimum conditions have been found, that is, the molar ratio of alcohol to acid is 1.2∶1.0 , the catalyst concentration 1%(mass fraction), the reaction time 2 h, the temperature 98—124 ℃ and a certain amount of polymerization inhibitor exists.

Synthesis and Characterization of Styrene-Maleic Anhydride-Butyl Acrylate Terpolymer

A novel surface modifying agent and internal compatilizer of inorganic and macromolecule composite materials,P(St/MAH/BA)terpolymer,was synthesized in butanone by solution polymerization method using styrene(St),maleic anhydride(MAH),and butyl acrylate(BA)as monomers and azobisisobutyronitrile(AIBN)as an initiator.Some affecting factors on terpolymers yields such as polymerization time,reaction temperature,solvent volume,initiator content,and reactants ratios were studied.Furthermore,the structure and thermal properties of terpolymers were primarily characterized and determined by Fourier Transform Infrared Spectroscopy(FTIR),nuclear magnetic resonance(NMR),thermogravimetric analysis(TGA),and gel permeation chromatography(GPC).The results indicate that the terpolymers are random polymers and the yields are low,but the thermal decomposed temperature of terpolymers P(St/MAH/BA)is around 220 ℃ and the average molecular weights(Mw)achieve 1.189×105 g·mol-1.

EFFECTS OF ω-ACRYLOYL POLY (ETHYLENE OXIDE) MACROMONOMER ON EMULSIFIER-FREE EMULSI0N COPOLYMERIZATION OF METHYL METHACRYLATE AND n-BUTYL ACRYLATE

Well-defined nonionic hydrophilic ω-acryloyl poly(ethylene oxide) macro-monomer (PEO-A) has been prepared by living anionic polymerization of ethylene oxidewith diphenyl methyl potassium as the initiator and acryloyl chloride as the reaction termi-nating agent. The polymer was characterized by FTIR and SEC. The emulsifier-free emul-sion polymerization of methyl methacrylate (MMA) and n-butyl acrylate (BA) containingvarious concentrations of PEO-A was studied. In all cases stable emulsion coplymerizationsof MMA and BA were obtained. The stabilizing effect was found to be dependent on themolecular weight and the feed amount of the macromonomer.

Acrylate Copolymers as Impact Modifi er for Epoxy Resin

P（BA-GMA）（PBG）, having various molecular weights, was synthesized by in situ polymerization of butyl acrylate（BA） and glycidyl methacrylate（GMA）, and further used as a modifier to improve the comprehensive properties of the epoxy curing system. The copolymers were characterized by gel permeation chromatography（GPC）. The effects of various molecular weights of copolymers on the mechanical properties, thermal performance, and phase behavior of the curing system were carefully evaluated. The experimental results of differential scanning calorimetry（DSC） and dynamic mechanical analysis（DMA） showed that glass transition temperature decreased and the tan δ peak shifted to a lower temperature with decreasing molecular weight of copolymer. Mechanical properties analysis of curing films showed that the impact strength and fracture toughness increased significantly upon the addition of PBG, indicating good toughness of the modified epoxy resins. From scanning electron microscopy（SEM） studies of the fracture surfaces of ER/PBG systems, the fracture behavior of epoxy matrix was changed from brittleness to toughness.

木质素磺酸钠-g-聚(ODA-co-BA)的制备及对水体有机污染物的吸附性能

可生物降解有机污染物吸附材料在处理水体有机物污染和有机危化品泄漏应急处理领域引起了广泛关注。为提高可降解有机污染物吸附材料的处置速度,采用悬浮聚合法,利用烯丙基木质素磺酸盐(SLS)部分代替甲基丙烯酸十八烷基酯(ODA),以丙烯酸丁酯(BA)、SLS和ODA为单体,二甲基丙烯酸-1,4-丁二醇酯(BDDMA)为交联剂、偶氮二异丁腈(AIBN)为引发剂,合成了Poly(SLS/ODA-co-BA)快速有机污染物吸附树脂。采用扫描电子显微镜(SEM)、X射线衍射(XRD)、差示扫描量热仪(DSC)、傅里叶变换红外光谱仪(FTIR)和热重分析仪(TG)等手段对快速有机污染物吸附树脂进行了表征,并以静态有机污染物吸附倍率、微分有机污染物吸附速率和重复利用率评价了其有机污染物吸附性能。结果表明,m(BA)∶m(ODA)∶m(SLS)=6.7∶1.9∶1.4制备的Poly(SLS/ODA-co-BA)共聚物有机污染物吸附性能最佳,对氯仿的吸附量高达18.9 g/g,其吸附平衡时间仅为1 h。SLS的添加使得有机污染物吸附树脂的平衡吸附速率快了5倍。此外,Poly(SLS/ODA-co-BA)有机污染物吸附树脂回收4次时,其对氯仿的吸附量仍大于初始吸附量的90%。

制备工艺对P(AN-BA)共聚乳液稳定性的影响

采用常规乳液聚合,在较高丙烯腈含量下制备了丙烯腈与丙烯酸丁酯共聚乳液,讨论加料方式、单体配比、乳化体系、乳化剂用量等对共聚乳液稳定性的影响,通过粒度仪、扫描电镜与透射电镜对乳液粒径和乳胶粒形貌进行表征。结果表明:一次加料法比单体预乳化滴加法所制得乳液粒径分布窄,平均粒径小;随丙烯腈质量分数的增加,乳液粒径分布变宽,平均粒径变大(从63 nm增加到140 nm);OP-10/SDS的复合乳化剂比Span80/SDS和PGPR/SDS的乳化效果更好;7.5 wt%OP-10/SDS复合乳化剂下制备的乳液平均粒径最小,为106.6 nm;所制备P(AN-BA)共聚乳胶粒呈核壳结构。

3D打印工艺参数对PLA/PTW共混物力学性能影响的研究

采用3D打印中的熔融沉积成型(FDM)工艺制备了聚乳酸/乙烯-丙烯酸丁酯-甲基丙烯酸缩水甘油酯共聚物(PLA/PTW),通过单因素实验探究了3D打印工艺参数(喷头温度、打印平台温度和打印速度)对PLA/PTW共混物力学性能的影响,并在此基础上设计了三因素三水平正交实验,优化了3D打印的工艺参数。结果表明,共混物的冲击强度和拉伸强度均随喷头温度的增加呈现先上升后下降、均随打印平台温度的增加而增加、均随打印速度的增加出现下降的趋势。各工艺参数对PLA/PTW共混物综合力学性能的影响从大到小依次为:喷头温度、打印速度、打印平台温度,且当喷头温度为210℃、打印平台温度为80℃以及打印速度为40 mm/s时,打印出的PLA/PTW共混物的综合力学性能最佳。

淀粉/BA-VAc接枝共聚物的合成及应用研究

以过硫酸铵为引发剂，研究了玉米淀粉与丙烯酸丁酯和醋酸乙烯酯接枝共聚合反应的规律。实验结果表明，单体浓度０．９７ｍｏｌ／Ｌ，引发剂浓度９．１×１０－３ｍｏｌ／Ｌ，反应温度６８℃，反应３ｈ时，反应体系的接枝率较高。通过红外光谱和Ｘ射线粉末衍射对接枝共聚物进行了结构分析。笔者以该接枝共聚物为基料，采用计算机辅助法设计出最优工艺配方。

超声无皂乳液聚合制备BA/St/AM三元共聚物乳胶粒及其聚合机理研究

将超声技术引入到无皂乳液聚合方法中,在不加入任何引发剂和乳化剂的情况下,制备了丙烯酸丁酯(BA)/苯乙烯(St)/丙烯酰胺(AM)三元共聚纳米乳胶粒.研究了不同超声时间对单体转化率、乳胶粒粒径以及乳液粘度的影响.同时还探讨了超声无皂乳液聚合机理,认为AM在聚合过程中起到了引发和稳定的作用.TEM照片表明,乳胶粒直径大约在80nm左右,FTIR及DSC分析表明产物为三元共聚物,而不是共混物.

VAc/BA核壳乳液聚合乳胶粒形态模拟

以醋酸乙烯酯和丙烯酸丁酯两种单体两阶段种子聚合制备核壳乳胶粒为例，研究了用簇迁移动力学模拟方法，进行对指定实验条件下核壳形态的预测，结果与实验相符。讨论了用简化的簇迁移动力学模拟方法进行核壳形态分子设计的进行步骤。

VAc/BA核壳乳液聚合乳胶粒形态演化

The morphological evolution of the latex particles obtained by VAc/BA two stage emulsion polymerization was studied. The designs of two group experiments were as follows:VAc as seed , BA was added in starved or overflown condition. The inverted core shell composite latex particles, with PVAc as shell and PBA as core, were found in overflown condition, however, the core shell composite latex particles, with PVAc as core and PBA as shell were found in starved condition. When the core shell composite latex particles in different time in starved condition was kept to reaction end, the morphology of the latex particles inverted. Comparing with the previous work in literature, this paper can provide better and more complete understanding about the morphological evolution of the latex particles in the process of seeded emulsion polymerization of VAc/BA. The photos of TEM of morphology of the latex particles in the process under two conditions and temperature being kept constant were obtained. From viscosity,the existed paradoxical views about the morphology of the latex particles on VAc/BA can be explained in a better and more complete way.

BA接枝改性聚丙烯纤维对水中邻苯二甲酸二丁酯的吸附

采用60Coγ射线共辐照的方法将丙烯酸丁酯(BA)接枝到聚丙烯(PP)纤维上,用红外光谱(IR)和扫描电镜(SEM)对接枝产物进行了表征.接枝纤维对邻苯二甲酸二丁酯(DBP)的吸附结果表明:该纤维对DBP的动力学吸附符合Lagergren二级动力学吸附模型,当DBP质量浓度为20 mg/L时,吸附在60 min达到平衡,平衡吸附量为5.04 mg/g;当DBP质量浓度为15 mg/L时,DBP去除效果最佳达到79.47%;当DBP质量浓度为10 mg/L时,接枝纤维对DBP的吸附容量达到2.88 mg/g,而原纤维在此浓度下对DBP的吸附容量仅为0.63mg/g,吸附能力提高了4.5倍.

PS/PBA自相容聚合物的浓乳液制备方法及其表征

利用浓乳液聚合反应速率快、便于界面反应等优点 ,提出了一种制备高分子合金的新方法。首先 ,分别将苯乙烯和丙烯酸丁酯单体的浓乳液体系进行预聚 ,然后将两体系混合 ,继续反应制得 PS/PBA自相容聚合物。研究了单体预聚转化率和共聚合温度等工艺参数对聚合物相容性的影响 ,并分别通过红外光谱法 (FT- IR)、扫描量热法 (DSC)、扫描电镜 (ESM)、透射电镜 (TEM)以及流变性能进行了表征。结果表明 ,在一定温度范围内 ,共聚反应温度越高 ,聚合物的相容性越好 ;而预聚转化率只有控制在一定范围内 。

PVC氯化原位接枝BA的合成与表征

采用气-固相搅拌式方法,氯气作为引发剂,在加热的情况下合成了聚氯乙烯(PVC)、丙烯酸丁酯(BA)的氯化原位接枝共聚产物(CPVC-g-BA)。用IR、1H-RNM等分析手段研究了PVC氯化原位接枝BA反应的可行性,以GPC等数据讨论了接枝共聚物的结构,并考察了反应温度、反应时间、单体用量对产物接枝率的影响:当加入20份BA,反应温度为120℃时,反应100 m in,接枝率达1.07%。

水解对乙烯-乙酸乙烯共聚物乳液复合的影响Ⅰ.EVA/BA复合体系

乙烯－ 乙酸乙烯共聚物（ＥＶＡ） 乳液在ＮａＯＨ 作用下进行表面水解处理后，加入丙烯酸丁酯（ＢＡ） ，在过硫酸铵引发下进行复合反应， 通过对复合乳胶粒的形态表征及胶膜的凝胶质量分数的测定、热分析及动态粘弹性表征，表明随ＥＶＡ 乳胶粒的表面水解程度的增大，ＢＡ 在胶粒表面的接枝率增大，体系的交联程度也增大。

室温界面自交联对PS/PBA乳胶IPN力学和阻尼性能的影响

利用种子乳液聚合以及双丙酮丙烯酰胺(DAAM)与己二酰肼和甲基丙烯酸缩水甘油醚(GMA)与乙二胺的交联反应合成了系列聚苯乙烯/聚丙烯酸正丁酯(PS/PBA)室温界面自交联乳胶互穿聚合物网络(IPN)。拉伸实验结果表明,自交联可提高LIPN的拉伸强度,减少永久形变,并且拉伸强度随DAAM和GMA用量的增加而增加。动态力学谱结果表明,自交联使LIPN的玻璃化温度升高以及阻尼性能下降,并且随DAAM用量的增加,阻尼性能降低;随GMA用量的增加,阻尼性能先增后降。GMA为5%时,LIPN具有较高的拉伸强度和阻尼性能。

氯化聚丙烯／MMA／BA／MAA接枝共聚物的合成

采用溶液法用混合单体甲基丙烯酸甲酯(MMA)、丙烯酸丁酯和2-甲基丙烯酸(MAA)对氯化聚丙烯(CPP)进行接枝改性,考察了反应温度、反应时间、引发剂浓度和单体浓度等因素对接枝率的影响,并对接枝产物进行了傅立叶变换红外光谱分析。确定了理想的工艺条件:反应温度为105℃,反应时间为5 h,m(CPP)/m(单体)/m (RPO)为1:0.3:0.03。

改变配比和加料方式进行VAc-BA的半连续乳液聚合

在５００ｍｌ反应釜中进行了７０℃，ＶＡｃ－ＢＡ的种子半连续乳液共聚实验，纯单体进料和乳液进料，改变单体配比和乳化刘的滴加比率进行实验。模型选用Ｓｚａｂｏ和Ｎａｕｍａｎ的近似速率表达式，并考虑ＶＡｃ在水相和有机相中的相分配，模拟结果良好，对设计和生产具有指导意义。

超声波无皂乳液制备BA/AM/纳米SiO_2复合材料

将超声波辐照技术引入到聚合物纳米材料的制备过程,通过超声产生的分散、活化及引发等作用实现纳米粒子分散的同时进行无皂乳液聚合,制备了丙烯酸丁酯(BA)/丙烯酰胺(AM)/纳米SiO2复合材料。实验结果表明,采用经丙烯酸丁酯表面改性后的纳米SiO2粒子,生成的乳液分散稳定性好。FT-IR及TEM证实了聚合物对纳米粒子的包裹。研究了超声波强度、超声辐照时间、单体配比等因素对单体转化率和聚合速率的影响。结果表明,提高超声波强度,延长超声辐照时间以及提高丙烯酰胺在单体配比中的含量,均能提高单体转化率和聚合反应速度。