抗氧剂MBP在ABS接枝共聚物中的稳定作用

在采用乳液聚合方法制备丙烯腈-丁二烯-苯乙烯（ABS）接枝共聚物时,将受阻酚类抗氧剂2,2′-亚甲基双（4-乙基-6-叔丁基苯酚）（MBP）以乳液的形式加到ABS胶乳中。通过对粉料进行动态和静态DSC分析和TG分析,测定粉料的拉伸性能和老化后的ABS接枝共聚物的黄色指数的变化等对不同含量的抗氧剂MBP在ABS中的稳定作用进行了研究。结果表明：当w（MBP）=0.1%时,即能对ABS接枝共聚物起到较好的保护作用;w（MBP）=1.5%的ABS接枝共聚物的断裂伸长率下降速度最快;其中当w（MBP）=1%时,ABS接枝共聚物的黄色指数在整个实验范围内最高。     

一种ABS抗氧剂乳液的制备方法

以油酸钾为乳化剂、对甲酚和双环戊二烯丁基化产物CPL为主抗氧剂、硫代二丙酸二月桂酯(DLTP)为辅抗氧剂,采用反向乳化法制得不同粒径、配比和固含量的抗氧剂乳液,并对其进行Zeta电位、表面张力和稳定性测试,然后将乳液加入丙烯腈-丁二烯-苯乙烯接枝共聚物(ABS胶乳)中进行耐老化性能测试。结果表明:采用反相乳化法可制得高效稳定的抗氧剂乳液。对于同配比的抗氧剂乳液,其粒径分布越窄,乳液稳定性越好。抗氧剂乳液的分散程度与主辅抗氧剂的配比共同决定着氧化诱导时间,而氧化诱导温度仅取决于主辅抗氧剂配比。     

渤海锦州9-3油田消泡剂的研究

以二甲基硅油为原料,白炭黑为添加剂制备的硅膏为消泡剂主剂,配合聚醚改性硅油、乳化剂、增稠剂和蒸馏水而成的乳液型消泡剂,在锦州9-3油田的现场评价中表现突出,优于平台现用的溶剂型消泡剂产品,其中硅膏10%、聚醚改性硅油15%、乳化剂1%、增稠剂0.5%、蒸馏水73.5%制成的乳液型消泡剂产品效果最佳,具有良好的推广和应用前景。     

基于快速热循环注塑工艺要求的ABS改性

在双螺杆挤出机上制备了能满足快速热循环注塑工艺要求的丙烯腈一丁二烯一苯乙烯三元共聚物（ABS）／聚甲基丙烯酸甲酯（PMMA）共混物,测试了力学性能和光学性能。结果表明,PMMA可提高ABS／PMMA共混物的拉伸强度、弹性模量和洛氏硬度．但降低了合金的冲击强度和断裂伸长率;抗氧剂抑制了聚合物共混过程中的氧化降解,提高了共混物的性能;在相同注塑工艺条件下,w（PMMA）为10％时,共混物的光泽度提高了4％。     

有机硅复配乳液消泡剂制备工艺的研究

二甲基硅油和二氧化硅混合得到硅膏,然后与聚醚、聚醚改性硅油、乳化剂和增稠剂等进行复配,制得有机硅聚醚乳液消泡剂。以消泡剂稳定性和消泡性能为检测指标,分别研究了消泡主体硅膏与聚醚的比例、乳化剂的HLB值、混合乳化剂的种类及添加量、增稠剂的种类及添加量对消泡剂的影响。结果表明,乳液中硅膏与聚醚的含量为20%,且两者比例为2∶3时,乳化剂HLB值应在7.7左右;采用混合乳化剂70%的Span60和30%的Tween80,用量为6%;选用0.75%的HPMC为增稠剂时,乳化效果最佳。     

有机硅复配乳液消泡剂制备工艺的研究

二甲基硅油和二氧化硅混合得到硅膏,然后与聚醚、聚醚改性硅油、乳化剂和增稠剂等进行复配,制得有机硅聚醚乳液消泡剂。以消泡剂稳定性和消泡性能为检测指标,分别研究了消泡主体硅膏与聚醚的比例、乳化剂的HLB值、混合乳化剂的种类及添加量、增稠剂的种类及添加量对消泡剂的影响。结果表明,乳液中硅膏与聚醚的含量为20%,且两者比例为2∶3时,乳化剂HLB值应在7.7左右;采用混合乳化剂70%的Span60和30%的Tween80,用量为6%;选用0.75%的HPMC为增稠剂时,乳化效果最佳。     

烃油乳液型消泡剂的制备及其在丁腈胶乳后处理中的应用

制备了烃油乳液型消泡剂,研究了原料、反应物配比、反应温度、反应时间、乳化体系及配比等对制备烃油乳液型消泡剂的影响;考察了该消泡剂在丁腈胶乳(NBRL)后处理中的应用效果,并与进口消泡剂进行了对比。结果表明,制备烃油乳液型消泡剂的最佳反应条件为高碳脂肪酸/烷基醇胺(质量比)为2.8/1,液体石蜡/高碳脂肪酸(质量比)为4.5/1,酯化反应温度为100℃,反应时间为3.5 h;在水溶液及NBRL体系中,烃油乳液型消泡剂与进口消泡剂相比,其消泡性能相当或更好;加入适量消泡剂,NBRL后处理装置泡沫抑制情况较好,对丁腈橡胶产品的性质及力学性能无不良影响。     

G-ABS胶乳后处理工艺对ABS产品白度与色差稳定性的影响

为了提高现有丙烯腈-丁二烯-苯乙烯聚合物(ABS)产品的白度,改善其色差的稳定性,增加产品在白色家电市场的竞争力,考察了接枝ABS(G-ABS)胶乳后处理工艺对ABS产品白度和色差稳定性的影响,主要包括抗氧剂加入温度、颜色改进剂加入方式和G-ABS胶乳凝聚浆液pH值。结果表明,温度对G-ABS粉料的抗氧化性能影响明显,在50℃时把乳液抗氧剂加入到G-ABS胶乳中所得到的G-ABS粉料氧化诱导期最长;ABS树脂的白度和冲击强度随着G-ABS凝聚浆pH值升高而增加,GABS凝聚浆液接近中性时,ABS树脂的耐高温老化和耐光氧老化性能最佳。向G-ABS胶乳中添加颜色改进剂等助剂能明显提高产品的白度、耐高温老化和耐光氧老化性能。     

电子束辐照对医用ABS材料的影响

ABS树脂是五大合成树脂之一,其在各个领域中具有相当广泛的应用。通过探究ABS辐照变色机理,设计实验探索不同抗氧剂的添加对ABS性能的影响。研究了辐照后主抗氧剂1010、抗氧剂1098和抗氧剂1076以及辅助抗氧剂626和168的添加量、主抗氧剂和辅抗氧剂相互复配对ABS的力学性能、扫描电镜、热性能、黄度的影响。测试结果表明:加0.5 phr主抗氧剂1076、0.5 phr主抗氧剂1010、0.3 phr主抗氧剂1098时,耐辐照效果良好;0.7 phr主抗氧剂1010和0.3 phr辅抗氧剂168复配、0.7 phr主抗氧剂1098和0.3 phr辅抗氧剂168复配时,黄度效果较好;辐照后材料拉伸强度、弯曲强度下降,冲击强度上升;从扫描电镜图可以看出,冲击缺口断裂形貌显示为韧性断裂;相比较辐照前,材料的热稳定性和玻璃化转变温度都有所增加。     

抗氧剂对ABS树脂加工稳定性的影响

通过测定ABS树脂的氧化诱导时间和氧化诱导温度及其在多次挤出前后熔融指数、黄色指数及微观结构的变化,研究了不同加工抗氧剂168、618、1076／168、1076／618对ABS树脂加工稳定性的影响。结果表明：四种抗氧体系均能使ABS树脂在多次挤出加工中保持良好的熔体稳定性,当抗氧剂168和618单独使用时,加入抗氧剂168和618的ABS树脂的热稳定性相当,但抗氧剂168能够更有效地抑制ABS树脂在加工过程中的黄变。当引入受阻酚类主抗氧剂1076后,其与亚磷酸酯类抗氧剂并用时的效果好于亚磷酸酯类抗氧剂单独使用时的效果。与其他抗氧剂相比,复合抗氧剂1076／168能够更好地保持ABS树脂在多次挤出加工中的各项性能。     

15％甲维·吡虫啉悬浮剂的研制

通过对润湿分散剂、防冻剂、增稠剂的筛选,确定了15％甲维·吡虫啉悬浮剂优惠配方：78．2％甲维盐原药6．5％,95．6％吡虫啉原药10．6％,润湿分散剂GY—SC853．0％,防冻剂尿素4．0％,增稠剂黄原胶0．2％、硅酸镁铝0．5％,消泡剂GY—X600．2％,水75．0％。该优惠配方制备的悬浮剂低温和热贮后物理化学性质稳定。     

PVC／ABS共混体系的相容性与形态结构研究

采用种子乳液聚合技术在聚丁二烯（PB）乳胶粒子上接枝共聚苯乙烯（St）、α-甲基苯乙烯（α—MSt）和丙烯腈（AN）单体,合成了一系列不同AN结合量的ABS和α—MABS接枝共聚物。将其与聚氯乙烯（PVC）树脂熔融共混制得了PVC／AtkS共混物,利用扫描电镜（SEM）、透射电镜（TEM）和动态力学分析仪（DMA）对共混物的相容性和相结构进行了表征。结果发现,在PVC／ABS共混体系中,尽管改变接枝SAN共聚物的AN结合量,PVC和ABS接枝共聚物均为不相容体系;在ABS接枝共聚物中引入α-MSt后,当接枝SAN共聚物的AN结合量为18．7％～23．6％（质量分数）时,共混物在室温以上只存在1个tanδ峰,共混物成为相容体系,当AN结合量达到32．1％（质量分数）时,共混物成为部分相容体系。共混物的相区尺寸明显地依赖于接枝SAN共聚物中的AN结合量,与动态力学性能结果表现出良好的吻合。     

Control of rheology of water-borne paints using associative thickeners

Water-borne decorative topcoats generally show inferior leveling and open time compared to solvent-based paints. Basically, this behavior is caused by the divergent viscosity–solid content relationship for dispersions and emulsions and by the relatively high evaporation rate of water. Employment of associative thickeners may improve leveling and open time of latex paints only if they introduce a substantial amount of ‘network viscosity,' characterized by a short relaxation time and little dependence on solid content. This network viscosity enables one to formulate a paint with sufficient high-shear viscosity at a particle-packing density far below the value where low-shear viscosity starts to diverge. Addition of an associative thickener not only affects rheology, but also the interaction between latex particles: Associative HEUR thickeners may induce undesired phase separation by strong bridging between the latex particles. The influence of HEUR thickeners on latex particle interaction has been studied by turbidity measurements. The experimental results could qualitatively be interpreted very well by two-particle interaction potentials computed using the Self-Consistent-Field theory of Scheutjens and Fleer. It is demonstrated how viscosity, created by the addition of an associative thickener to a highly concentrated latex, can be split up into a polymer network viscosity and a contribution to (relative) dispersion viscosity. According to these analyses, reduction of the molecular weight of tri-block HEUR thickeners yields an increase of the favorable network viscosity and a reduction of the unfavorable dispersion viscosity. However, reduction of the molecular weight of the HEUR thickener is limited by the introduction of undesired phase separation (bridging flocculation) below a certain molecular weight.     

环氧官能化ABS增韧PBT树脂的性能研究

采用乳液聚合方法合成了甲基丙烯酸环氧丙酯(GMA)共聚的丙烯腈/丁二烯/苯乙烯核壳粒子ABS-g-GMA,用于不同分子量聚对苯二甲酸丁二醇酯(PBT)的增韧。红外光谱证明GMA接枝共聚到了ABS粒子上。DMA测试发现PBT与ABS、ABS-g-GMA之间有一定的相容性。SEM表明ABS-g-GMA均匀分散在不同分子量的PBT树脂中。ABS-g-GMA可以实现对PBT树脂的有效增韧,PBT树脂的分子量越大,增韧效率越高,共混物的断裂伸长率越大。     

Effect of temperature and type of food simulant on antioxidant stability

Additive migration levels in food simulants from polimeric materials that are intended to be into contact with food can be affected by additive stability under the migration test conditions. In this work, the stability of some phenolic antioxidants and one oxidized phosphite antioxidant was studied in four food simulants: distilled water, 3% (w/v) acetic acid, 10% (v/v) ethanol, and the fatty food simulant olive oil, under different temperatures 5, 40, and 70°C, during ～20 days. Samples were analyzed by reversed‐phase high performance liquid chromatography (HPLC) with UV diode‐array detector. In general, antioxidants appeared to be more stable in olive oil than in the aqueous simulants. Among aqueous simulants, water and 10% ethanol allowed the highest stability of antioxidants at low temperatures. The 3% acetic acid allowed good stability for the lowest phenolic compounds even at high temperatures, but the highest molecular weight compounds decomposed very fast even at low temperatures. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 656–663, 2006     

Interaction between styrene/butylacrylate latex and water soluble associative thickener for coalescent free wall paints

The effect of water soluble hydrophobically modified ethylene oxide urethane (HEUR) thickener on coalescent free wall paints was studied. Three systems were looked at: latex/thickener blends, model paints (containing no fillers that could have an effect on paint rheology) and satin paints (PVC 30%). The latexes used were a styrene/butylacrylate copolymer, designed for coalescent free wall paints. A full factorial statistical experimental design was employed to study the effect of latex and formulation variables on the viscosity response for the full range of shear rates encountered in paint application. The factors considered in the design were total latex surface area, polymerization surfactant level, thickener type and thickener concentration. The surfactant level was varied between 0.85 and 1.71 parts. The two HEUR thickeners were selected based on the manufacturer's claim that they exhibited good performance at different shear rates. The thickener levels were the extremes recommended by the manufacturer. Measurements were done on Haake, Rheometrics, Brookfield and ICI Cone & Plate rheometers. Total latex surface area and the thickener level are the two significant parameters for latex thickener blends and for model paints at the same significance level, this indicates good correlation between the two systems. The introduction of clay as a filler decreases the effect of all parameters studied.     

聚氨酯缔合型增稠剂的合成及其应用性能研究

介绍了两款聚氨酯缔合型增稠剂(HEUR)的制备方法,包括一款假塑型增稠剂(增稠剂-万华A)和一款牛顿型增稠剂(增稠剂-万华B),并在乳胶漆配方中考察了这两种增稠剂的增稠性能、配方稳定性、色浆稳定性及展色性;并考察了自制增稠剂B的增稠效率及其在水性木器涂料中的应用。研究表明:合成的自制增稠剂A具有优异的增稠剂效率、良好的配方稳定性、色浆稳定性及展色性。自制增稠剂B具有高效的高剪切增稠效率,在水性木器涂料中性能表现优异,性能良好。     

六苯氧基环三磷腈对PC/ABS合金的阻燃作用

通过极限氧指数测定(LOI)、垂直燃烧试验和锥型量热分析研究了六苯氧基环三磷腈(HPTCP)对聚碳酸酯/丙烯腈-苯乙烯-丁二烯共聚物(PC/ABS)合金的阻燃作用。结果表明:HPTCP对PC/ABS具有良好的阻燃效果。当添加量为15%时,阻燃PC/ABS的LOI为25.0%,阻燃等级达FV-0,并且与未阻燃PC/ABS相比,燃烧时的热释放速率、总热释放量、最高热释放速率、平均热释放速率,平均有效燃烧热和质量损失明显降低;热重分析表明,HPTCP对PC/ABS合金的热稳定性影响较小。热重和残余物分析结果表明,HPTCP主要是通过凝聚相产生阻燃作用,HPTCP的添加可有效抑制PC/ABS的分解,促进它成炭,形成膨胀性炭层,该炭层通过隔热、隔氧及阻止PC/ABS分解产物的挥发而产生阻燃作用。     

Recycling of dry and wet polyamide 6

Recycling of polycondensation polymers can give rise to secondary materials with good mechanical properties only if a careful drying is carried out before the melt reprocessing operations. The presence of humidity provokes the hydrolytic chain scission of the macromolecules and the consequent decrease of molecular weight and properties. In this work, the drying step was substituted by the addition of an antioxidant that is able to protect the macromolecules because it is the autioxidant is more prone to hydrolysis, thus removing the water from the melt. The mechanical properties of polyamide 6 reprocessed more times in wet conditions and in the presence of this stabilizer are even better than those obtained reprocessing the dry polyamide. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1899–1903, 2002     

单组分室温交联丙烯酸酯微乳液木器涂料配方研究

采用自制的丙烯酸酯微乳液配制了单组分室温交联木器涂料,对成膜助溶剂、润湿流平剂、消泡剂、增稠剂等助剂进行了筛选,并通过正交试验对各助剂的最佳用量进行了确定。结果表明,由丙二醇单丁醚和二丙二醇单丁醚构成的混合成膜助溶剂,其添加量在4%较为适宜;润湿流平剂BYK346的适宜添加量为0.4%;消泡剂FoamStar-A34添加量为0.4%较为适宜;缔合型增稠剂Rheolat 212适宜用量为0.7%。