丙烯酸酯核壳纳米粒子的合成及其改性环氧树脂

以丙烯酸丁酯(BA)为软单体、甲基丙烯酸甲酯(MMA)为硬单体和甲基丙烯酸缩水甘油脂(GMA)为官能单体,采用乳液聚合法合成出具有活性结构的BA/MMA/GMA核壳纳米粒子,并以此作为环氧树脂(EP)的增韧改性剂。研究结果表明:当w(核壳粒子)=10%、m(BA):m(MMA):m(GMA)=80:20:10时,与纯EP体系相比,改性EP体系的断裂伸长率提高了42.5%,剥高强度提高了近3倍,25℃和150℃时的剪切强度分别提高了48.6%和31.2%,坡璃化转变温度变化不大;红外光谱(FT-IR)证实,该核壳纳米粒子具有典型的特征吸收峰;透射电镜(TEM)观察结果表明,合成粒子具有纳米级核壳结构。     

UV固化丙烯酸酯胶粘剂的合成及性能研究

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酸缩水甘油酯(GMA)和丙烯酸羟乙酯(HEA)为共聚单体,并以二缩三丙二醇二丙烯酸酯(TPGDA)为交联剂、十二烷基硫醇(NDM)为链转移剂和乙酸乙酯为极性溶剂,采用核/壳溶液聚合法合成了侧链含C=C的丙烯酸酯预聚体;然后以此为基体树脂、丙烯酸异冰片酯(IBOA)和三羟甲基丙烷二丙烯酸酯(TMPTA)为活性稀释剂、651为自由基光引发剂和碘鎓盐为阳离子光引发剂,制备了UV固化胶粘剂。研究结果表明:合成丙烯酸酯预聚体的最佳工艺条件是m(BA)∶m(MMA)∶m(GMA)∶m(TPGDA)∶m(HEA)=20∶60∶10∶4∶6、n(TPGDA)∶n(NDM)=2∶2、w(热引发剂)=3%和w(乙酸乙酯)≥70%(均相对于共聚单体总质量而言);自由基/阳离子混杂双重UV固化胶粘剂比单一自由基UV固化胶粘剂具有更大的附着力和耐酸碱性,此时前者的最佳配方中w(预聚体)=55%、w(651或碘鎓盐)=5%、w(IBOA)=15%、w(TMPTA)=12%和w(GMA)=8%(均相对于胶粘剂总物料质量而言)。     

丙烯酸酯阴极电泳涂料用树脂的合成与表征

采用甲基丙烯酸环氧丙酯(GMA)与丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)聚合制备丙烯酸酯阴极电泳涂料用主体树脂,并对所合成的主体树脂进行胺化。利用红外及核磁共振碳谱分析了胺化反应机理,证明是开氧环反应。     

沉淀聚合制备GMA型聚丙烯酸酯

采用沉淀聚合法以乙二醇单甲醚与去离子水为分散介质,在没有使用稳定剂的情况下,成功地合成了甲基丙烯酸缩水甘油酯(GMA)-甲基丙烯酸甲酯(MMA)-丙烯酸丁酯(BA)三元共聚聚丙烯酸酯(简称GMA型聚丙烯酸酯)。用质量分析法测试了单体转化率,利用扫描电子显微镜、红外光谱仪与核磁共振氢谱仪和凝胶渗透色谱仪研究了GMA型聚丙烯酸酯粒子的形貌及分布,表征了树脂的结构,在107.0℃条件下,树脂的数均分子量和相对分子质量分布指数分别为5 895和1.61。通过调整m(MMA):m(BA),可以调控GMA型聚丙烯酸酯的玻璃化转变温度在50.0~70.0℃。树脂的环氧值0.17~0.20 mol/g。该树脂适用于粉末涂料中。     

光热双重固化聚丙烯酸酯压敏胶的制备及性能研究

采用溶液聚合法合成了一系列由不同丙烯酸酯和甲基丙烯酸环氧丙酯(GMA)组成的共聚物,其中w(GMA)=3%;然后将该共聚物与丙烯酸羟丙酯(HPA)、交联剂和可见光引发剂等混合均匀,涂布后在可见光照射和加热双重作用下进行交联固化,制取聚丙烯酸酯压敏胶。结果表明:当共聚物中m(BA)∶m(MMA)=85∶15、w(交联剂)=3%、w(HPA)=12%、w(光引发剂)=1.5%和光照时间为2min时,压敏胶的综合性能最佳,其剥离强度高达11.3N/25mm。     

SiO_2改性含氟丙烯酸酯乳液性能研究与表征

以甲基丙烯酸甲酯(MMA)、甲基丙烯酸–β–羟丙酯(β–HPMA)和丙烯酸六氟丁酯(F6BA)为单体,采用乳液聚合法制备P(MMA/β–HPMA/F6BA)乳液,并通过正硅酸四乙酯(TEOS)在碱性条件下水解得到的SiO2对乳液进行共混改性。研究了复合乳化剂用量、引发剂用量对乳液稳定性的影响。FT–IR分析表明,得到了目标产物;DSC分析表明,随TEOS用量的增加,共聚物玻璃化转变温度增大;激光粒度(LPS)分析表明,加入少量的TEOS使乳胶粒子的粒径显著增大,聚合物的粒径呈正态分布。     

可UV固化丙烯酸酯乳液的制备

采用预乳化工艺,半连续种子聚合法,通过MMA、St、BA、AA共聚反应制得高酸值的丙烯酸酯乳液,然后向其中引入甲基丙烯酸缩水甘油酯(GMA)制得带有碳碳双键的乳液,使其具有可UV固化性能。结果表明,经过甲基丙烯酸缩水甘油酯改性的乳液涂膜的耐水性得到了明显的提高,经过UV光固化后涂膜的耐水性、硬度、耐划伤性、抗粘连性都得到较大的改善;而且当乳液树脂酸值为80mgKOH/g以及GMA的添加量为75%左右时所得乳液涂膜的综合性能达到最优。经红外光谱测试得出GMA与乳液中的羧基发生了化学反应而不是简单的物理混合。     

POSS改性BMI树脂固化动力学及固化工艺研究

以双马来酰亚胺(BMI)、二烯丙基双酚A(BA)和七苯基倍半硅氧烷三硅醇(POSS-triol)为原料,采用非等温差示扫描量热(DSC)法研究了BMI/BA/POSS-triol体系的固化反应过程。运用Kissinger极值法、Crane法、Flynn-Wall-Ozawa(FWO)等转化率法和T-β(温度-升温速率)外推法确定了改性树脂体系的固化反应动力学参数和固化工艺参数。结果表明:改性树脂体系的固化反应活化能和反应级数(接近于1)均随POSS-triol用量增加而变化不大,说明POSS-triol的加入并没有明显改变BMI/BA体系的固化反应机理;改性树脂体系的凝胶温度为175.7℃,固化温度为226.9℃,后处理温度为271.7℃。     

磷酸酯丙烯酸防锈乳液的制备

以MMA/BA/AA/GMA/HEA/磷酸酯(PAM100)为聚合单体,利用种子乳液法合成了磷酸酯丙烯酸防锈乳液,讨论了交联单体、磷酸酯、反应型乳化剂对乳液性能的影响。结果表明:磷酸酯的加入可提高涂层的附着力。该乳液与传统的苯丙乳液相比,拥有更好的钙离子稳定、防锈性能、湿态附着力,具有良好的市场推广价值。     

水性光固化丙烯酸酯聚丙烯酸酯的合成研究

以甲基丙烯酸甲酯(MMA)、甲基丙烯酸(MAA)、丙烯酸正丁酯(BA)等为原料制备出羧基型丙烯酸酯树脂;然后,滴加甲基丙烯酸缩水甘油酯(GMA),与丙烯酸酯树脂进行接枝反应;最后,在减压条件下脱除溶剂,加入中和剂进行中和,加水进行分散,制备得到了水性光固化丙烯酸酯聚丙烯酸酯树脂。实验发现:引发剂用量为6%、催化剂用量为2.5%、阻聚剂为2%、甲基丙烯酸缩水甘油酯(GMA)用量为15%、酸值为50 mg KOH/g,接枝反应温度为110℃时,得到的水性光固化丙烯酸酯聚丙烯酸酯树脂的固含量为35%,黏度约1 800 m Pa·s,树脂可获得良好的性能。     

MMA—BA—MAA树脂自由基共聚合成的研究

以过氧化二苯甲酰为引发剂,采用溶液聚合合成了甲基丙烯酸甲酯（MMA）．丙烯酸丁酯（BA）＋甲基丙烯酸（MAA）树脂,通过实验确定了自由基共聚合适宜的单体配比、单体浓度、引发剂浓度、溶剂以及反应的升温速度。该改性后的丙烯酸树脂可作为胶粘剂的大分子固化剂,能提高粘接强度和透明性。     

Internal stress of epoxy resin modified with acrylic core-shell particles prepared by seeded emulsion polymerization

In order to reduce the internal stress in a cured epoxy resin, the submicron polymer particles were dispersed therein prior to curing. For this purpose, four kinds of poly(butyl acrylate), poly(methyl methacrylate) core-shell particles were prepared by seeded emulsion polymerization for methyl methacrylate with poly(butyl acrylate) seed particles having different particle diameter, and subsequently were powdered by drying at room temperature. It was observed by SEM that poly(butyl acrylate) particles as core were dispersed in the cured epoxy matrix. Poly(methyl methacrylate) as shell seems to dissolve in the matrix. The internal stress of cured epoxy resin decreased with the modification of the particles and the tendency was enhanced with a decreasing in the particle diameter.     

粉末涂料用GMA型丙烯酸树脂的合成及其固化分析

利用甲基丙烯酸甲酯、甲基丙烯酸缩水甘油酯(GMA)、丙烯酸丁酯进行自由基聚合合成GMA型丙烯酸树脂。研究固化剂十二烷基二元酸用量、固化时间、固化温度、升温速率对涂层性能及固化过程的影响。结果表明树脂与固化剂用量比为10:2,固化条件为160℃固化30min,制备的丙烯酸粉末涂料具有良好的性能。     

Internal stress of epoxy resin modified with acrylic core-shell particles containing functional groups prepared by seeded emulsion polymerization

In order to reduce the internal stress in a cured epoxy resin, submicrometer-sized poly(butyl acrylate) (PBA)/poly(methyl methacrylate) (PMMA) core-shell particles having cross-links were dispersed in the resin prior to curing. For the introduction of cross-links, monoethylene glycol dimethacrylate or glycidyl methacrylate monomer was copolymerized. Cross-links in the PBA core reduced the shrinkage of the cured epoxy resin, and cross-links at the PMMA shell produced a strong interaction with the epoxy matrix. The internal stress was reduced effectively by the introduction of cross-links.     

Effects of poly(methyl methacrylate)‐based low‐profile additives on the properties of cured unsaturated polyester resins. I. Miscibility,curing behavior,and glass‐transition temperatures

The effects of three series of self‐synthesized poly(methyl methacrylate) (PMMA)‐based low‐profile additives (LPAs), including PMMA, poly(methyl methacrylate‐co‐butyl acrylate), and poly(methyl methacrylate‐co‐butyl acrylate‐co‐maleic anhydride), with different chemical structures and MWs on the miscibility, cured‐sample morphology, curing kinetics, and glass‐transition temperatures for styrene (ST)/unsaturated polyester (UP) resin/LPA ternary systems were investigated by group contribution methods, scanning electron microscopy, differential scanning calorimetry (DSC), and dynamic mechanical analysis, respectively. Before curing at room temperature, the degree of phase separation for the ST/UP/LPA systems was generally explainable by the calculated polarity difference per unit volume between the UP resin and LPA. During curing at 110°C, the compatibility of the ST/UP/LPA systems, as revealed by cured‐sample morphology, was judged from the relative magnitude of the DSC peak reaction rate and the broadness of the peak. On the basis of Takayanagi's mechanical models, the effects of LPA on the final cure conversion and the glass‐transition temperature in the major continuous phase of ST‐crosslinked polyester for the ST/UP/LPA systems was also examined. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3369–3387, 2004     

水稀释丙烯酸酯分散体及其双组分涂料的制备研究

以甲基丙烯酸甲酯、丙烯酸丁酯、甲基丙烯酸丁酯、甲基丙烯酸为主要单体,采用自由基溶液聚合和相反转的方法合成了水稀释丙烯酸酯树脂分散体（WPA）。加入聚碳化二亚胺类固化剂（PCDI）进行交联固化,得到双组分丙烯酸酯树脂涂料。探讨了影响该分散体性能的各种因素,并对交联固化反应机理和条件进行了研究,运用FT-IR、DSC对树脂进行结构表征。结果表明：当甲基丙烯酸占单体总量的8%,引发剂占1.5%,链转移剂占0.4%,溶剂与单体总量比为0.3∶1.0时分散体性能较好;当固体分质量比WPA/PCDI为3∶1~5∶1时,涂膜先在60℃闪蒸15 min,然后常温放置72h,双组分涂膜性能较佳。     

环氧树脂室温固化用柔性固化剂的制备与性能研究

首先将聚醚多元醇和甲基丙烯酸甲酯(MMA)进行酯交换反应,然后利用多元胺与烯双键的加成反应原理,将多乙烯多胺与甲基丙烯酸酯进行反应,合成了含甲基丙烯酸聚醚多元醇酯柔性基团的新型环氧树脂室温固化剂。通过FT-IR等方法对产物结构进行表征,探讨并优化了各种反应条件,最后考察了该柔性固化剂对环氧树脂性能的影响。研究结果表明,柔性固化剂合成反应的优化条件是n(聚醚多元醇)∶n(MMA)为1∶5,n(催化剂)∶n(聚醚多元醇+MMA)为2∶100,n(聚醚多元醇酯)∶n(多乙烯多胺)为1∶2.0,反应时间为8h;在此条件下所得固化剂的产率和收率分别为96.3%和96.38%;改性固化剂/环氧树脂体系的凝胶时间仅为29min,拉伸剪切强度达到30MPa。     

紫外光固化低黏度环氧丙烯酸酯的合成研究

以双酚F环氧树脂和丙烯酸为原料,合成紫外光固化低黏度双酚F型环氧丙烯酸酯。讨论了引发剂、阻聚剂、反应温度等因素对反应的影响,用IR对环氧树脂及环氧丙烯酸酯的结构进行了表征。     

Effect of naphthyl curing agent having thermally stable structure on properties of UV-cured pressure sensitive adhesive

Pressure sensitive adhesives (PSAs) with higher thermal stability were synthesized by crosslinking acrylic copolymer with naphthyl curing agent. The acrylic copolymer was synthesized for a base resin of PSAs by solution polymerization of 2-ethylhexyl acrylate, ethyl acrylate, and acrylic acid with N,N′-azobisisobutyronitrile as an initiator. The acrylic copolymer was further modified with glycidyl methacrylate to have the vinyl groups available for UV curing. Thermal stability of acrylic PSAs was improved noticeably with increasing naphthyl curing agent content and UV dose mainly due to the extensive formation of crosslinked structure in the polymer matrix. Although the peel strength decreased with UV curing of acrylic polymer, a proper balance between the thermal stability and the adhesion performance of PSAs was obtained by controlling the UV curing with naphthyl curing agent content and UV dose.     

环氧树脂改性醇溶性双组分复膜胶的研制

首先以EP(环氧树脂)和MAA(甲基丙烯酸)为原料,合成了EM(甲基丙烯酸环氧单酯);然后以EM、HPA(丙烯酸羟丙酯)、VAc(醋酸乙烯酯)和EA(丙烯酸乙酯)为共聚单体,制得四元共聚物(EM环氧改性聚丙烯酸酯);最后将其和自制氨基聚氨酯固化剂作为双组分,两者共混后制得醇溶性复膜胶。研究结果表明:采用单因素试验法优选出制备EM环氧改性聚丙烯酸酯的最佳工艺条件是反应温度为75℃、反应时间为6 h、w(引发剂)=1.6%(相对于混合单体总质量而言)和m(EA)∶m(VAc)∶m(EM)∶m(HPA)=41∶28∶17∶14;当m(氨基)∶m(环氧基)=20∶21、固化时间为24 h和固化温度为50℃时,复膜胶的剥离强度相对最大。