悬浮聚合法制备ASA树脂及其性能研究

采用悬浮聚合法,以丙烯酸丁酯、苯乙烯和丙烯腈为原料,合成了一系列丙烯酸丁酯-苯乙烯-丙烯腈(ASA)树脂。考察了橡胶相聚丙烯酸丁酯(PBA)、甲基丙烯酸烯丙酯(ALMA)和叔十二碳硫醇(TDDM)用量对ASA树脂的力学性能影响。结果表明:PBA质量分数达到20%后,ASA树脂的冲击强度大幅增加。TDDM的加入使苯乙烯-丙烯腈(SAN)的相对分子质量降低,当其质量分数低于1%时,ASA树脂的冲击强度呈升高趋势,质量分数高于1%时其冲击强度大幅降低。随PBA含量增加,ASA树脂的拉伸强度减小,断裂伸长率变大。     

AES树脂的制备及其性能研究

采用乳液聚合法,以三元乙丙橡胶(EPDM)、苯乙烯和丙烯腈为原料,合成一系列丙烯腈-三元乙丙橡胶-苯乙烯(AES)接枝共聚物,与苯乙烯-丙烯腈共聚物(SAN)树脂共混制备AES树脂,考察了橡胶相EPDM和相对分子质量调节剂十二烷基硫醇(TDDM)的用量对AES树脂的冲击强度的影响;以及EPDM质量分数对AES树脂的拉伸强度和断裂伸长率的影响。结果表明,EPDM质量分数超过15%后,AES树脂冲击强度大幅度增加;TDDM的质量分数为1%时,AES树脂的冲击强度达到最大值;随着EPDM用量增加,AES树脂的拉伸强度减小,断裂伸长率变大。     

不同交联剂对ASA核壳聚合物增韧性能影响

为考察交联剂对丙烯酸丁酯-苯乙烯-丙烯腈塑料(ASA)接枝塑料增韧性能的影响，使用丙烯酸双环戊二烯基酯(DCPA)、三烯丙基异氰脲酸酯(TAIC)和三烯丙基脲酸酯(TAC)三种不同的交联剂制备了一系列核壳结构的ASA，再将其与苯乙烯-丙烯腈塑料(SAN)熔融共混制得ASA/SAN共混物。通过测算接枝率和差示扫描量热测试，证明成功合成ASA接枝聚合物。利用冲击测试仪、电子拉力机对共混物力学性能进行分析。结果表明，使用TAIC交联剂制备的ASA/SAN共混物缺口缺口冲击强度最高达到170.4 J/m，高于DCPA和TAIC交联剂。对比三种交联剂的拉伸强度与断裂伸长率，发现使用TAIC的ASA/SAN共混物拉伸强度略低于其它两种，断裂伸长率没有明显区别。动态力学分析仪考察了不同交联剂对ASA/SAN共混物动态力学性能的影响，发现低温区的玻璃化转化温度不同，说明交联剂会对橡胶相的玻璃化转化温度产生影响。     

不同改性剂对ABS力学性能的影响

研究了改性剂种类及其含量对(丙烯腈/苯乙烯/丁二烯)共聚物(ABS)力学性能的影响.结果表明,ABS/(丙烯腈/苯乙烯/丙烯酸酯)共聚物(ASA)共混体系的冲击强度最高;ABS/ABS胶粉共混体系的缺口冲击强度最高;ASA和ABS胶粉对ABS拉伸强度的影响最小.(苯乙烯/丁二烯/苯乙烯)嵌段共聚物(SBS)的质量分数为25%时,ABS的断裂伸长率最高.扫描电子显微镜观察发现,ABS/ABS胶粉共混试样断面发生的屈服程度较大.加入少量相容剂,ABS的力学性能并不能得到明显改善.     

PBA-g-SAN对ASA树脂结构与性能的影响

采用种子乳液聚合方法,合成一系列苯乙烯-丙烯腈共聚物接枝聚丙烯酸丁酯（PBA-g-SAN）核壳接枝共聚物,将其与苯乙烯-丙烯腈共聚物（SAN树脂）熔融共混,制得ASA树脂,使用动态力学分析仪和扫描电子显微镜考察了扩径中接枝剂的含量和PBA橡胶粒径对ASA树脂性能的影响。结果表明,随着接枝剂含量的增加,PBA-g-SAN接枝共聚物的接枝率升高,当接枝剂占单体BA的3%时,ASA树脂的冲击强度达到110 J/m。ASA树脂的冲击强度随着橡胶粒径的增加先升高后降低。PBA-g-SAN接枝共聚物中PBA的玻璃化转变温度(（Tg）随着接枝剂含量的增加而升高,随着PBA橡胶粒径的增加先降低后升高。当PBA橡胶粒径为92.7 nm时,橡胶粒子发生聚集,其他粒径的PBA橡胶均可较好地分散在基体中。     

橡胶含量对ABS树脂性能的影响

采用聚丁二烯接枝苯乙烯-丙烯腈共聚物(PB-g-SAN)与苯乙烯-丙烯腈共聚物(SAN)熔融共混,制备了一系列丙烯腈-丁二烯-苯乙烯共聚树脂(ABS),考察了橡胶含量对该ABS树脂物理力学性能的影响。结果表明:随着橡胶含量的增加,ABS树脂的拉伸强度、弯曲强度、弯曲模量、熔体流动速率、热变形温度、密度和硬度均有所降低,而缺口冲击强度和断裂伸长率提高。因此可通过调节橡胶含量来制备具有不同物理力学性能的ABS树脂,以满足不同的应用需要。     

马来酸酐官能化ASA对PA6的增韧研究

采用乳液聚合法制备了一系列马来酸酐（MAH）官能化的丙烯酸丁酯橡胶（PBA）与苯乙烯（St）及丙烯腈（AN）的接枝共聚物（PBA-g-SAN）核壳结构改性剂（ASA-g-MAH）,用于聚酰胺6(PA6)的增韧。Molau实验证实了PA6/ASA-g-MAH共混体系中存在化学反应,考察了MAH含量对共混体系结构和性能的影响。结果表明,随着MAH含量的增加,PA6/ ASA-g-MAH共混物的冲击强度逐渐增大,当MAH含量为4 %（质量分数,下同）时材料冲击强度达到1008 J/m;与PA6/ASA共混物相比,PA6/ASA-g-MAH共混物具有较高的拉伸强度和断裂伸长率;随着MAH含量的增加,ASA- g-MAH在PA6基体中的分散程度越来越好,当MAH含量达到4 %以上时,无聚集现象发生;ASA-g-MAH中橡胶粒子的空洞化和PA6基体的剪切屈服是主要的增韧机理。     

PBA-g-SAN的表征及其对SAN树脂的增韧作用

以乳液聚丙烯酸丁酯(PBA)为主链,苯乙烯(St)和丙烯腈(An)为接枝单体,通过乳液接枝共聚合成了PBA-g-SAN接枝共聚物,用SEM、FTIR和DSC对其进行了表征。以PBA-g-SAN与SAN树脂共混制备ASA,用DSC和SEM分别对ASA及其冲击断面进行了分析。结果表明,PBA-g-SAN以平均粒径为85nm的微粒连接成珠链状的形态存在,具有高接枝率,PBA相与SAN相部分相容;PBA-g-SAN在SAN树脂中有良好的分散性,ASA存在Tg为10℃左右的界面相,使PBA相与SAN相结合紧密;当PBA质量分数为25%时,ASA的冲击断面呈“须根”结构,证实其增韧机理为剪切屈服机理。上述结构赋予ASA以高抗冲性能,其缺口冲击强度最高可达33 kJ/m2。     

ABS/改性抗菌纳米ZnO的力学及抑菌性能

采用偶联剂处理法对抗菌纳米ZnO表面进行改性,制备了丙烯腈-丁二烯-苯乙烯共聚物(ABS)／改性抗菌纳米ZnO复合材料。结果表明:改性抗菌纳米ZnO质量分数为3％时,复合材料的改性效果最佳,其拉伸强度、断裂伸长率、硬度、缺口冲击强度和无缺口冲击强度分别较纯ABS树脂提高37．4％,3．4％,44．0％,15．8％,11．8％;复合材料对大肠杆菌、金色葡萄球菌的抑菌率分别达到76．3％及84．0％。     

ABS树脂的冲击韧性极限及形变机理的研究

将苯乙烯-丙烯腈共聚物接枝聚丁二烯（PB-g-SAN）与苯乙烯-丙烯腈共聚物（SAN）树脂按照一定比例熔融共混制备具有不同橡胶含量的丙烯腈-丁二烯-苯乙烯共聚物（ABS）树脂。研究了不同橡胶含量对ABS树脂的冲击以及拉伸行为的影响,并通过透射电子显微镜研究了ABS树脂的微观形态及形变机理。结果表明,ABS材料的冲击强度随着橡胶含量的增加先升高后降低;断裂伸长率随着橡胶含量的增大而增大;当橡胶含量较少时,橡胶粒子在基体相中发生聚集现象的可能性较小,分散性较好;随着橡胶含量的增加发生聚集现象的可能性增加,粒子分散性变差;随着橡胶粒子含量的增加,ABS树脂的主要增韧机理是由空洞化到银纹再到剪切屈服的转变。     

丙烯酸酯接枝改性天然橡胶增韧聚乳酸

通过在天然橡胶(NR)分子链上接枝甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA),制备了三种丙烯酸酯接枝改性NR:NR-g-PMMA,NR-g-PBA和NR-g-(PMMA,PBA)。采用核磁共振氢谱对三种接枝物进行了化学结构鉴定。将接枝改性后的NR和未改性的NR与PLA采用哈克密炼机熔融共混,分别制备了PLA/NR,PLA/NR-gPMMA,PLA/NR-g-PBA和PLA/NR-g-(PMMA,PBA)共混物,研究了接枝改性NR和未改性NR含量对共混物力学性能和热性能的影响。各共混物的拉伸弹性模量和拉伸强度均随接枝改性NR和未改性NR含量的增加而降低,断裂伸长率和缺口冲击强度随接枝改性NR和未改性NR含量的增加而提高。其中,PLA/NR-g-PBA共混物的断裂伸长率和缺口冲击强度比其它共混物提高的幅度大,当NR-g-PBA的质量分数为5%时,PLA/NR-g-PBA共混物的断裂伸长率达到78%,缺口冲击强度为5.2 k J/m2,而纯PLA的断裂伸长率仅为7.7%,缺口冲击强度为2.5 k J/m2,说明NR接枝分子柔顺性较高的BA更有利于促进其与PLA共混物的韧性提高。热分析结果表明,PLA/NR-gPBA共混物的热稳定性相比于纯PLA也有所提高。     

Toughness,dynamic mechanical property,and morphology of polyvinylchloride/acrylonitrile‐styrene‐butyl acrylate blends

Acrylonitrile‐styrene‐butyl acrylate (ASA) graft copolymers with different acrylonitrile (AN) contents, the core‐shell ratio, and tert‐dodecyl mercaptan (TDDM) amounts were synthesized by seed emulsion polymerization. Polyvinylchloride (PVC)/ASA blends were prepared by melt blending ASA graft copolymers with PVC resin. Then the toughness, dynamic mechanical property, and morphology of the PVC/ASA blends were investigated. The results indicated that the impact strength of the PVC/ASA blends increased and then decreased with the increase of the AN content in poly(styrene‐co‐acrylonitrile (SAN) copolymer, and increased with the increase of the core‐shell ratio of ASA. It was shown that brittle‐ductile transition of PVC/ASA blends was dependent on poly(butyl acrylate) (PBA) rubber content in blends and independent of AN content in SAN copolymer. The introduction of TDDM made the toughness of PVC/ASA blends poor. Dynamic mechanical analysis (DMA) curves exhibited that PVC and SAN copolymers were immiscible over the entire AN composition range. From scanning electron microscopy (SEM), it was found that the dispersion of ASA in PVC/ASA blends was dependent on the AN content in SAN copolymer and TDDM amounts. J. VINYL ADDIT. TECHNOL., 22:43–50, 2016. © 2014 Society of Plastics Engineers     

Toughening of polylactide with natural rubber grafted with poly(butyl acrylate)

Natural rubber grafted with poly(butyl acrylate) (NR‐g‐PBA) in an attempt to toughen polylactide (PLA) was prepared by grafting butyl acrylate onto natural rubber (NR) through emulsion polymerization. The purified NR‐g‐PBA was confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. NR‐g‐PBA/PLA blend and NR/PLA blend were prepared with a Haake internal melt mixer. The morphology and mechanical properties of the blends were investigated as a function of rubber content. Observations by scanning electron microscopy showed that the spherical‐particle‐dispersed phase appearing in the NR/PLA blend was not found in the NR‐g‐PBA/PLA blend, which showed that NR grafted with PBA is compatible with PLA, and accounted for the efficient toughening effect on PLA. The elongation at break and the impact strength were significantly improved with an increase in NR‐g‐PBA content. The thermal stability of PLA decreased when blended with NR but was retained with NR‐g‐PBA. Copyright © 2011 Society of Chemical Industry     

接枝剂对PBA/P(MMA-ITA)核壳粒子的制备影响及其增韧聚酰胺6的研究

摘要：研究了接枝剂：甲基丙烯酸烯丙酯（ALMA）对聚丙烯酸丁酯/聚(甲基丙烯酸甲酯-衣康酸)(PBA/P(MMA-ITA))型核壳粒子的制备及其增韧尼龙6的影响。探讨了ALMA用量对核壳粒子平均粒径、凝胶含量、增韧尼龙6的力学性能和加工性能的影响。实验数据显示,接枝剂提高了凝胶含量,但对平均粒径没有影响。引入适量的ALMA可以使增韧尼龙6的冲击强度和拉伸强度分别达到20kJ/m2和35MPa;熔体黏度、结晶度和熔点均降低。利用扫描电子显微镜(SEM)观察增韧尼龙6断面的形态,表明PBA/P(MMA-ITA)核壳粒子增韧尼龙6符合空穴化理论。     

纳米SiO2／水性丙烯酸树脂复合材料的制备及工艺研究

以甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸为原料,纳米SiO2为改性剂,通过原位聚合法和共混法制备了水性丙烯酸树脂纳米复合材料。研究了纳米粒子的加入量对树脂硬度、拉伸强度、断裂伸长率、耐候性、热稳定性的影响,利用IR、TEM、TG等测试技术对纳米SiO2／水性丙烯酸树脂进行了表征。试验结果表明：纳米SiO2的加入使聚丙烯酸酯分子链之间增加了交联度,其力学性能有所提高;随着纳米SiO2含量的上升,硬度和拉伸强度都有较大的增加,而吸水率和断裂伸长率相应减小。同时由原位聚合法制备的水性丙烯酸树脂纳米复合材料的热分解温度也要高于共混法制备的水性丙烯酸树脂纳米复合材料。     

Irradiation‐induced surface graft polymerization onto calcium carbonate nanoparticles and its toughening effects on polypropylene composites

Nano‐sized calcium carbonate was pretreated with silane coupling agent and then mixed with butyl acrylate that is of larger amount than the nanoparticles. Under γ‐irradiation, graft polymerization occurred on the nanoparticle surface, forming a nanocomposite structure consisting of grafted poly(butyl acrylate) (PBA), homopolymerized PBA, and the segregated nanoparticles. It was found that the silane pretreatment significantly promoted the graft reaction. When the grafted nano‐CaCO₃ particles were melt compounded with polypropylene (PP), an obvious synergistic effect, offered by (i) the chemical bonding between the elastomer type grafted PBA and nano‐CaCO₃ and (ii) the deliberately introduced thick interlayer mainly constructed by the homopolymerized PBA, led to a significant increase in notch impact strengths and elongation to break of PP at a rather low content of nano‐CaCO₃. Meanwhile, the tensile stiffness of the composites was also slightly increased and the yielding strength of the composites was almost unchanged. The results are different from those with conventional rubber‐toughened plastics, in which the improvement of ductility is acquired at high additive fraction and a great expense of strength performance. POLYM. ENG. SCI., 45:529–538, 2005. © 2005 Society of Plastics Engineers     

丁基橡胶热氧老化性能的研究

通过改变配方中酚醛树脂的用量和卤素给予体的种类及用量,探讨了各变量下对IIR硫化特性和耐热氧老化性能的影响。实验表明,老化前后,300%定伸应力和硬度均有所提高,而拉伸强度、撕裂强度和拉断伸长率有不同程度下降。在树脂用量为8份、CIIR用量为11份、BIIR用量为9份时,各配方的IIR硫化胶性能最好。     

Modification of novolac resin by interpenetrating network formation with poly(butyl acrylate)

Interpenetrating networks (IPNs) of novolac (phenol formaldehyde) resin and poly(butyl acrylate) (PBA) were prepared by a sequential mode of polymerization. Both full IPNs and semi‐IPNs of different compositions were synthesized and characterized with respect to their mechanical properties, that is, their modulus, ultimate tensile strength (UTS), elongation‐at‐break percentage, and toughness. Their thermal properties were examined with differential scanning calorimetry and thermogravimetric analysis (TGA). A morphological study was performed with an optical microscope. The effects of the variation of the blend ratios on the aforementioned properties were studied. There was a gradual decrease in the modulus and UTS with a simultaneous increase in the elongation‐at‐break percentage and toughness for both types of IPNs as the proportions of PBA were increased. With increasing proportions of PBA, the glass‐transition temperatures of the different IPNs underwent shifts toward a lower temperature region. This showed a plasticizing influence of PBA on the rigid and brittle phenolic matrix. TGA thermograms depicted the classical two‐step degradation for the phenolic resin. Although there was an apparent increase in the thermal stability at the initial stage (up to 350°C), particularly at lower temperatures, a substantial decrease in the thermal stability was observed at higher temperatures under study. In all the micrographs of full IPNs and semi‐IPNs, two‐phase structures were observed, regardless of the PBA content. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2407–2417, 2005