变温聚合工艺对聚合反应速率及PVC树脂性能的影响

分别采用恒温和变温聚合工艺合成聚氯乙烯(PVC)树脂,研究了PVC树脂的基本性能。结果表明:采用变温聚合工艺,在压力下降阶段提高聚合温度制备PVC树脂,可提高聚合反应速率,树脂热稳定性和颗粒性能合格。与恒温聚合工艺所制树脂相比,变温聚合工艺所制PVC树脂的聚合度下降约40,相对分子质量分布由2.05增至2.15,热稳定性略有提高;较宽的相对分子质量分布改善了树脂的加工性能,据此优化加工配方可使制品保持良好的力学性能。     

硬质型材用PVC树脂S-1000A的开发与应用

研究了树脂颗粒形态和平均聚合度对聚氯乙烯（PVC）加工性能的影响，通过改善生产工艺、调整聚合配方，开发出具有颗粒形态好、平均聚合度适中的硬质型材专用PVC树脂，满足了新型进口生产线的高速加工要求。     

PVC注塑管件专用树脂的开发

介绍了以生产SG-7型PVC树脂为基础,在30m3聚合釜上,通过对生产配方与工艺参数的调整,解决分子量控制、降低鱼眼、颗粒形态优化和提高热老化性等方面问题,开发出塑化性能好,具有较好流变性和耐热性,适于PVC注塑管件加工的专用树脂。     

氯乙烯-丙烯酸酯共聚树脂的性能及应用

选用3种不同基本性能的氯乙烯-丙烯酸酯共聚树脂(以下简称氯丙树脂),研究其作为PVC加工改性剂、冲击改性剂及注塑专用树脂时的加工应用特点。结果表明:1作为加工改性剂时,1.5份氯丙树脂A与2份加工型ACR的改性效果相当;2作为冲击改性剂时,在用量较少的情况下氯丙树脂B可替代CPE;3作为注塑专用树脂时,氯丙树脂C具有塑化时间短、塑化温度低、熔体黏度小、流动性好等特点,且试样的冲击性能比普通PVC注塑料大幅提高,但断裂强度有所降低。     

PVC-U管件专用料的研制

介绍了PVC—U管件专用料的研制过程,采用S-700作为基体PVC树脂,采用铅盐系列作为配方的稳定体系,合理调整内外润滑剂构成润滑体系,用ACR-401作为冲击改性剂。测试结果表明：该PVC管件专用料具有良好的力学性能、成型加工性和热稳定性,管件性能达到相关技术标准要求。     

S-500型低聚合度PVC树脂的开发研究

研究了S-500型低聚合度PVC树脂的合成技术,确定了使用链转移剂合成S-500型PVC树脂的聚合配方和工艺条件。结果表明:S-500型PVC树脂相对分子质量分布集中,颗粒规整度好,粒度分布集中,熔体流动速率较高,加工塑化性能良好。     

表面改性纳米碳酸钙原位悬浮聚合PVC的制备与性能研究

采用湿法表面改性的纳米碳酸钙(nano-CaCO3)与VCM原位聚合,制备了nano-CaCO3原位聚合PVC树脂(简称原位PVC树脂),研究了其力学性能、加工性能、微观形貌和热稳定性等。结果表明:①nano-CaCO3能够很好地分散在PVC树脂中,对PVC基体产生很好的补强作用;与普通PVC试样相比,原位PVC试样缺口冲击强度提高到13.3 kJ/m2,效果显著;其加工性能也得到了提高。②试样冲击断面的扫描电子显微镜照片表明原位PVC试样为韧性断裂,普通PVC试样为脆性断裂。③DSC试验表明,原位PVC树脂的热稳定性优于纯PVC树脂。     

电石法与乙烯法PVC材料的性能对比

研究了电石法与乙烯法PVC材料性能的差别,比较了二者的分子质量及其分布、流变性能和力学性能。针对试验中考察的PVC树脂样品而言：①电石法PVC树脂的分子质量比乙烯法PVC树脂低,其分子质量分布比乙烯法PVC树脂宽;②电石法PVC干混料的塑化性能优于乙烯法PVC干混料;③电石法与乙烯法PVC树脂的力学性能相差不大。     

本体法与悬浮法PVC树脂生产工艺的比较及在管件生产中的优势

比较了本体法PVC7型树脂与悬浮法PVC-SG7型的生产工艺,介绍了本体法PVC树脂的质量、塑化性能和加工性能等在管件生产中的优势。     

SG-5型PVC下水管件专用料研制与应用

经过改进流动性的以SG—5型PVC树脂为基料的下水管件注塑专用料,其流动性能接近SG—7型PVC树脂专用料。SG—5型专用料注塑的管件制品具有强度高、成本低、较易加工等特点,可完全替代SG—7型专用料。工业化生产后,经济效益明显。     

氯乙烯/丙烯酸酯二元及多元共聚物的研究进展

介绍了氯乙烯/丙烯酸酯多元共聚物、聚氯乙烯树脂/丙烯酸酯/顺丁烯二酰亚胺接枝共聚物、聚氯乙烯树脂/N-取代马来酸胺/丙烯酸酯接枝共聚树脂、氯乙烯/乙酸乙烯/丙烯酸羟丙酯共聚物、氯乙烯/乙酸乙烯/丙烯酸丁酯共聚乳液、聚丙烯酸酯-氯乙烯接枝共聚物、氯乙烯/乙烯/丙烯酸羟乙酯共聚涂料树脂、氯乙烯/丙烯酸甲酯共聚乳液的特点、生产工艺及其性能和用途.     

VC-BA树脂替代ACR对PVC性能的影响

研究了VC—BA树脂（即氯乙烯一丙烯酸丁酯共聚树脂）与ACR对PVC干混料的加工性能、试样的力学性能的影响。结果表明：VC—BA树脂与PVC相容性良好。它的加入促进了PVC体系的熔融,改善了干混料的塑化性能,提高了试样的力学性能,可以替代ACR,是性能良好的PVC改性剂。     

特种聚氯乙烯树脂生产概况

简述了国内外主要特种聚氯乙烯树脂(包括高聚合度PVC树脂、消光PVC树脂、PVC掺混树脂、氯乙烯一醋酸乙烯共聚树脂和氯化PVC树脂)的生产情况。并列举了主要特种PVC树脂的生产厂商、牌号和技术规格。     

Acrylonitrile-styrene-acrylate particles with different acrylonitrile contents for improving the toughness of poly(vinyl chloride) resin

Poly(butyl acrylate) grafted styrene and acrylonitrile copolymer (PBA-g-SAN, ASA) with core–shell structures were prepared by emulsion polymerization technology to improve the toughness of the poly(vinyl chloride) (PVC). The mechanical properties of the PVC/ASA blends were investigated. The notch impact strength of the PVC/ASA blend could reach 1200 J/m when the 13 phr ASA was added to the PVC. This was several times more than pure PVC resin. Scanning electron microscopy analysis results indicated that the improvement in impact strength of the PVC/ASA blend was attributed to shear yielding induced by ASA particles. Additionally, subtle changes in the ratio of monomers in the shell layer led to significant fluctuations in the mechanical properties of the composites. Dynamic mechanical analysis showed that the intermolecular interaction forces between ASA particles and PVC resins played a key role in improving the toughness of PVC/ASA blend.     

氯乙烯-丙烯酸丁酯共聚树脂的工业化生产

在7m3聚合釜中采用悬浮聚合工艺工业化生产了氯乙烯-丙烯酸丁酯共聚树脂,在小试配方基础上调整了分散剂的配比和用量,采用在线实时示踪剂色谱联动控制法控制丙烯酸丁酯的加入速度,并采用了聚合中途注水工艺及改进的防粘釜工艺。工业化产品符合企业标准要求,可在PVC型材生产中替代ACR使用。     

管件专用聚氯乙烯树脂的生产

简述了管件专用聚氯乙烯树脂在上海天原化工有限公司的30m^3聚合釜的生产情况,对生产中的配方和工艺进行了调整和优化,生产出聚合度为700的管件专用聚氯乙烯树脂的干流动性和流变性能接近日本信越TK-700聚氯乙烯树脂的实测水平。     

Dynamic mechanical,rheological, and morphological studies of polyacrylate-graft-poly (vinyl chloride) suspension resin

A series of polyacrylate-graft-poly (vinyl chloride) (ACR-g-PVC) resins were prepared through suspension graft copolymerization. Three kinds of polyacrylate latices were grafted by vinyl chloride using suspension polymerization method at 57 ± 0.1°C, respectively. The dynamic mechanical and rheological properties and the morphology of the resulting ACR-g-PVC resins were investigated. Poly (butyl acrylate)-graft-poly (vinyl chloride) (PBA-g-PVC) resin exhibited better toughness, and the optimized content of PBA in ACR-g-PVC resin was 6–8 wt%. The melt viscosity of ACR-g-PVC resin was much lower than that of pure PVC. The nature of the fracture surfaces of ACR-g-PVC material indicated that it has good toughness. The impact strength of the PBA-g-PVC material was greatly improved compared with that of pure PVC. The Young's modulus of the ACR-g-PVC material containing less than 15 wt% of PBA was comparable to that of pure PVC according to their dynamic mechanical analysis curves. For all of the ACR-g-PVC resins, there were two individual relaxations in the low-temperature range. One was β transition of PVC, and the other was α transition of ACR. The glass transition temperature of PVC in the ACR-g-PVC resin shifted to lower temperature when the content of the PBA was above 50 wt%. POLYM. ENG. SCI., 47:996–1003, 2007. © 2007 Society of Plastics Engineers     

Rheological behavior and thermal properties of poly(butyl acrylate‐co‐2‐ethylhexyl acrylate)‐grafted vinyl chloride resin

The rheological behavior and thermal properties of a poly(butyl acrylate‐co‐2‐ethylhexyl acrylate) [P(BA‐EHA)]‐grafted vinyl chloride (VC) composite resin [P(BA‐EHA)/poly(vinyl chloride) (PVC)] and its materials were investigated. The rheological behavior, thermal stability, and Vicat softening temperature (VST) of P(BA‐EHA)/PVC were measured with capillary rheometry, thermal analysis, and VST testing, respectively. The effects of the P(BA‐EHA) content and the polymerization temperature of grafted VC on the rheological behavior of the composite resin were examined. The weight loss of the composite resin and its extracted remainder via heating were analyzed. The influence of the content and crosslinking degree of P(BA‐EHA) and the polymerization temperature of the grafted VC on VST of the materials was determined. The results indicated the pseudoplastic‐flow nature of the composite resin. The flow property of the modified PVC resin was improved because of the incorporation of the acrylate polymer. The molecular weight of PVC greatly influenced the flow behavior and VST of the composite resin and its materials. The flowability of the composite resin markedly increased, and the VST of its materials decreased as the polymerization temperature of the grafted VC increased. The initial degradation temperature of the composite resin increased as the P(BA‐EHA) content increased. The VST of the samples was enhanced a little as the content of the crosslinking agent increased in P(BA‐EHA). As expected, the composite resin, with good impact resistance, had better heating stability and flowability than pure PVC, whereas the VST of the material decreased little with increasing P(BA‐EHA) content. Therefore, P(BA‐EHA)/PVC resins prepared by seeded emulsion polymerization have excellent potential for widespread applications. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 419–426, 2005     

ARGET ATRP法合成聚氯乙烯接枝丙烯酸丁酯共聚物

以不稳定氯含量高的聚氯乙烯（U-PVC）和氯乙烯-溴代异丁酸烯丙酯共聚物（PVC-co-ABrMP）为大分子引发剂,使用电子转移催化再生原子转移自由基聚合（ARGET ATRP）进行丙烯酸丁酯（BA）的溶液接枝共聚。在固定CuCl₂：三（2-吡啶甲基）胺：辛酸亚锡（摩尔比）时,当CuCl₂用量（相对于氯乙烯链节数）小于0.1%时,BA转化率随CuCl₂用量增加而明显增加;辛酸亚锡与CuCl₂摩尔比大于50时,辛酸亚锡用量对聚合速率的影响较小;相同催化体系用量下,采用PVC-co-ABrMP为引发剂,可获得更高的BA转化率。通过PVC-co-ABrMP酯基水解得到PBA支链,其分子量分布指数为1.29,符合“活性”自由基聚合的特征。接枝PBA对PVC有明显的内增塑效果,PBA摩尔分数为32.75%的PVC-g-BA的玻璃化温度为8.34℃。