核/壳乳胶粒的形态结构和粒径

本文研究了聚苯乙烯/聚丙烯酸2-乙基已酯和聚苯乙烯/聚丙烯酸丁酯核/壳乳胶粒的形态和结构,并研究了乳化剂和单体用量及加入方式对乳胶粒径的影响,结果表明乳胶粒径具有翻转核/壳结构,核/壳层之间形成了接枝共聚物。乳胶粒径随壳单体用量的增加而增加,而壳单体的加入方式对乳胶粒径影响较小。     

聚丙烯酸丁酯接枝共聚物的可控合成及作为相容剂的应用

结合电子转移再生催化剂原子转移自由基聚合(ARGET ATRP)和普通自由基聚合,制备了一系列聚丙烯酸丁酯接枝共聚物,详细研究了其作为苯乙烯-丙烯腈共聚物树脂/丙烯酸酯橡胶(SAN/ACM)共混体系的相容剂,在制备丙烯腈-苯乙烯-丙烯酸酯树脂(ASA树脂)时,不同主链结构、侧链相对分子质量、接枝密度及用量对增容效果的影响。通过傅里叶变换红外光谱仪和凝胶渗透色谱仪对聚合物结构进行测试和表征;采用动态力学分析仪(DMA)和冲击试验机研究了共混物的力学性能。结果表明,成功制备了不同结构的聚丙烯酸丁酯接枝共聚物,以苯乙烯-丙烯腈共聚物(SAN)作为主链比聚丙烯酸丁酯(PBA)作为主链的接枝共聚物具有更好的增容效果。此外,侧链PBA的相对分子质量较小时,侧链与主链摩尔比为3∶1及相容剂用量为3%(质量分数)时,接枝共聚物的增容效果最佳。DMA分析表明添加接枝共聚物后SAN和ACM两组分的玻璃化转变温度相互靠近,聚丙烯酸丁酯接枝共聚物起到了明显的增容作用。     

聚丙烯酸-g-聚(卤代)苯乙烯两亲性接枝共聚物的可控合成

以丙烯酸甲酯、(卤代)苯乙烯为原料,利用原子转移自由基聚合技术、从主干接枝的合成策略和聚丙烯酸甲酯的碱性水解,实现了两亲性接枝共聚物聚丙烯酸-g-聚(卤代)苯乙烯的可控合成.主链和侧链的分子量可分别通过调整单体与引发剂的投料比和反应时间进行控制.(卤代)苯乙烯单体接枝共聚时,采用单体过量的本体聚合且单体转化率控制在10...     

聚硅氧烷-g-聚丙烯酸酯乳液接枝共聚的研究

以含活性点的聚硅氧烷为主链,以丙烯醚丁酯（ＢＡ）、甲基丙烯酸甲醌（ＭＭＡ）为接枝单体,通过乳液接枝共聚合合成了聚硅氧烷－ｇ－聚丙烯酸酯接枝共聚物,通过对产物的分离过程,红外光谱和核磁共振谱分析,对接枝物进行了表征,研究了加料方式、乳化剂用量、引发剂用量、反应温度和用配比等对单体转化率、接枝效率和交联度的影响;研究了部分工艺的乳液的粒子形态。     

含聚丙烯酸丁酯刷的羽毛接枝共聚物制备的研究

以羽毛为原料,丙烯酸丁酯(BA)为单体,采用电子转移活化再生催化剂原子转移自由基聚合(ARGET ATRP)方法,使BA在羽毛表面自增长,制备了聚丙烯酸丁酯刷的羽毛接枝共聚物。通过红外光谱(FT-IR)对改性前后羽毛的结构进行表征。探讨了接枝工艺中单体浓度、催化剂浓度、配体与催化剂配合比、还原剂与催化剂配合比、反应时间和反应温度对羽毛表面改性接枝率的影响。结果表明,BA接枝改性羽毛的最佳条件为:BA浓度为3mol/L,催化剂浓度为1.8mmol/L,配体与催化剂摩尔配合比为5∶1,还原剂与催化剂摩尔配合比为1∶1,反应时间8h,反应温度60℃,制得的聚丙烯酸丁酯刷的羽毛接枝共聚物的接枝率达到32%。     

PBA-g-PS对ACR/PS共混体系性能的影响

采用大单体技术合成聚苯乙烯和丙烯酸丁酯的规整接枝共聚物PBA-g-PS.研究了共聚合反应条件:聚苯乙烯大单体的投料质量分数,引发剂用量,反应温度对接枝效率的影响;PBA-g-PS可以作为ACR/PS体系的共混增容剂,研究共混物的组成,接枝物的用量,接枝物的组成对共混物物理机械性能的影响.用SEM,DSC表征共混物的变化,结果表明,接枝共聚物确实能促进两组分相容,起到增容剂的作用.     

CA-g-PBA共混改性聚砜超滤膜的研究

以丙烯酸丁酯为单体,硝酸铈铵为引发剂,采用水相自由基界面聚合法制备醋酸纤维素接枝聚丙烯酸丁酯共聚物(CA-g-PBA)。将此共聚物作为添加剂,考察了CA-g-PBA的添加量对聚砜超滤膜结构和性能的影响。通过红外、热重分析,结果表明:采用水相自由基界面聚合反应成功制备了CA-g-PBA。CA-g-PBA和聚砜两相的相容性较聚砜-醋酸纤维素提高,超滤膜强度提高,热稳定性提高。     

乳化剂对复合胶粒核－壳结构的影响

采用半连续种子乳液聚合技术合成了聚丙烯酸丁酯／聚（甲基丙烯酸甲酯－交联单体）共聚物乳液。探讨了第二步乳化剂用量及添加方式对复合胶粒核－壳结构的影响     

聚丙烯接枝丙烯酸丁酯吸油纤维的制备和表征

采用紫外辐射引发的方法,在主要利用毛细管力作用吸油的聚丙烯纤维上接枝聚丙烯酸丁酯,制备了高吸油纤维.研究了影响聚丙烯纤维接枝率的因素,如辐照时间、单体浓度、光敏剂浓度等.用衰减全反射傅立叶红外光谱对接枝前后的纤维进行了表征,结果表明丙烯酸丁酯被成功接枝到PP纤维上.随着接枝率的增大,吸油纤维对柴油的吸附量先增大后减小....     

聚羟基烷酸酯与聚丙烯酸丁酯复合材料的相容性及生物降解性能研究

研究了用液相和固相反应性共混使聚丙烯酸丁酯 (PBA)与羟基丁酸 戊酸共聚物(PHBV)复合后 ,其接枝率和均聚物含量对复合物相容性、结晶性和生物降解性的影响 ,比较了不同试样在土壤中降解后的重量损失和形貌变化 ,结果表明PBA的接枝不利于PHBV的结晶和生物降解性 ,当PHBV PBA含量比为 6 0 4 0时 ,接枝率下降和均聚物含量增加至 2 0 4 % ,导致复合物两相明显不溶 ,土壤中降解后重量损失大大下降 ,而且微生物对PHBV PBA的侵蚀仅仅发生在表面PHBV相中     

Wetting behavior of oleophobic polymer coatings synthesized from fluorosurfactant-macromers

Architecturally similar monomers were copolymerized with a water-oil discriminate fluorosurfactant to create hydrophilic-oleophobic coatings. Acrylic acid, hydroxyethyl methacrylate, and methyl methacrylate were used as comonomers with the fluorosurfactant macromer. The homopolymers of the selected comonomers are water-soluble, water-swellable, and water-insoluble, respectively, thus coupling the surfactant monomer in varying concentration within polymers of varying hydrophilicity. Wetting behavior of water and hexadecane were examined as a function of copolymer composition, thus revealing critical structure-property relationships for the surfactant-based system. Acrylic acid copolymers and hydroxyethyl methacrylate copolymers both exhibited a hexadecane contact angle which exceeded the water contact angle. This condition predicted an ability to "self-clean" oil-based foulants. The most oleophobic of the self-cleaning copolymers had an advancing hexadecane contact angle of 73° and an advancing water contact angle of 40°. It was determined that the advancing and receding water and hexadecane contact angle response varies montonically for each copolymer type as the surface concentration of the surfactant is varied. Comparing between copolymer types revealed large differences in wetting response. Methyl methacrylate copolymers with 2.8 mol % surfactant had advancing water contact angle 82° and advancing hexadecane contact angle 26°, which is neither oleophobic nor self-cleaning. In contrast, acrylic acid copolymers with 3.1 mol % surfactant had advancing water contact angle of 44° and advancing hexadecane contact angle of 52°, creating a self-cleaning coating. Thus, the nature of the comonomer exerts a greater influence than the surfactant content on the wetting behavior and self-cleaning ability of the final coating.     

丙烯酸十八酯共聚物的合成及性能研究

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸十八酯(SA)作为单体合成丙烯酸酯乳液。通过改变乳化剂种类及SA用量,考察其对乳液聚合稳定性、共聚物的光泽度及拉伸性能、共聚物结晶行为的影响。结果表明:以A/FC-4430作为复合乳化剂所制备的乳液性能较好。随着SA用量的增加,共聚物膜的光泽度下降,而其拉伸强度先减小后增大。DSC分析发现,当SA的摩尔分数大于3%后,较多的SA侧链之间更易发生结晶行为,共聚物的结晶度升高。     

稳定自由基存在下嵌段共聚物的合成及表征

合成了一系列不同分子量，分子链末端带有稳定自由基（2，2，6，6－四甲基－1－哌啶氧化物，TEMPO）的聚苯乙烯大分子引发剂，分别引发甲基丙烯酸丁酯（BMA），甲基丙烯酸乙酯（EMA），甲基丙烯酸甲酯（MMA），甲基丙烯酸辛酯（OMA），醋酸乙烯酯（VAc)，二甲基丙烯酰胺（DMA），丙烯酸二甲胺基乙酯（DAEA）等7种极性单体形成两嵌段共聚物，聚苯乙烯－聚甲基丙烯酸酯嵌段共聚物的分子量可控，分子量分布较窄，单体转化率较高，醋酸乙烯酯和丙烯酸二甲胺基乙酯在相同条件下的嵌段共聚难以达到高转化率，嵌段共聚物经GPC和1H0NMR表征。     

丙烯酸酯与甲基丙烯酸酯的共聚及性能研究

采用悬浮聚合法，以丙烯酸－２－乙基－己酯与甲基丙烯酸十二酯为单体，合成了共聚型高吸油性树脂。研究了共聚单体的配比、交联剂用量、引发剂用量诸因素对高吸油性树脂的性能影响。制得的树脂可以吸其自身质量的１１．８倍的煤油、１４．７倍的苯、６．５倍的泵油。     

丙烯酸共聚物的合成及其制备阳极电沉积光致抗蚀剂研究

以丙烯酸(AA)、丙烯酸异辛酯(EHA)和苯乙烯(St)为单体通过自由基溶液共聚制备了阴离子型丙烯酸共聚物PESA,利用甲基丙烯酸缩水甘油醚(GMA)与PESA上羧基的开环反应合成一系列不同酸值的光敏共聚物G-PE-SA,经三乙胺(TEA)中和、去离子水乳化后成阳极电泳乳液。用核磁共振氢谱(1 H-NMR)、凝胶渗透色谱(GPC)、差示扫描量热法(DSC)、热重分析(TGA)、粒度分析仪考察了共聚物的结构和性能、乳液的粒径分布情况。结果表明:合成了目标产物G-PESA,初步研究了以光敏共聚物G-PESA为主体的负型光致抗蚀剂的应用性能,分辨率可达40μm。     

Monitoring of high solids content starved-semi-batch emulsion copolymerization reactions by Fourier transform Raman spectroscopy

A high solids content n-butyl acrylate/methyl methacrylate emulsion copolymerization process carried out under starved semi-batch conditions was for the first time monitored on-line by means of Fourier transform (FT)-Raman spectroscopy. Partial least squares regression was employed to build calibration models that allowed relating the spectra with solids content (overall conversion), free amounts of both n-butyl acrylate (n-BA) and methyl methacrylate (MMA), and cumulative copolymer composition. In spite of the heterogeneous nature of the polymerization, the similarities of the spectra for MMA, n-BA, and for the copolymer, and the low monomer concentrations in the reactor, the FT-Raman spectroscopy has been shown to be a suitable noninvasive sensor to accurately monitor the process. Therefore, it is well suited for on-line control of all-acrylic polymerization systems.     

Synthesis and properties of siloxane-containing hybrid hydrogels with alpha,omega-functionalized macromers

Siloxane-containing transparent hybrid hydrogels, coupled with high oxygen permeability and moderate equilibrium water content (EWC), were successfully obtained through free radical bulk copolymerization of hydrophobic and hydrophilic monomers. Due to obvious incompatibility of hydrophobic tris(trimethylsiloxy)-3-methacrryloxypropylsilane (TRIS) and hydrophilic 2-hydroxyehtyl methacrylate (HEMA) or N-vinyl pyrrolidone (NVP) monomers, alpha,omega-methacrylate terminated poly(dimethyl siloxane) (PDMS) macromer was employed as a compatibilizer in the formulations, resulting in high optical transmittance (> 90% at 400 nm) of the hybrid hydrogels. Although properties such as EWC and oxygen permeability of the hybrid hydrogels could be tailored over a wide range, the formulations with the PDMS macromer could not increase both EWC and oxygen permeability of the hybrid hydrogels without sacrificing one of them. For controlling these two properties simultaneously, an amphiphilic alpha,omega-methacrylate terminated PEO-PDMS-PEO triblock copolymer was synthesized as a surface-active macromer, and showed its usefulness in controlling phase separation and improving oxygen permeability and EWC, at the same time, of the hybrid hydrogels.     

两亲性丙烯酸酯共聚合的动力学研究

利用过氧化苯甲酰 (BPO)为引发剂探讨了甲基丙烯酸 β-羟乙酯 (HEMA)和丙烯酸十六烷基酯(RA)的自由基共聚合。重点讨论了该共聚反应的动力学方程 ,求出了这两种单体的竞聚率。并用 IR、13 C- NMR等手段对共聚物进行了表征     

分散聚合法制备粉末涂料用丙烯酸酯树脂

以偶氮二异丁腈为引发剂、聚乙烯吡咯烷酮为分散剂、乙醇-水混合溶剂为分散介质,采用甲基丙烯酸缩水甘油酯、甲基丙烯酸甲酯和丙烯酸丁酯为共聚单体,合成了含有环氧基的丙烯酸酯树脂;考察了丙烯酸丁酯量对共聚物微球形态的影响、反应时间与转化率的关系、丙烯酸酯树脂的玻璃化温度和环氧值等物性;利用合成的丙烯酸酯树脂,配合适当的助剂,制备出加工性能优异的丙烯酸酯粉末涂料。