Influence of ABS type on morphology and mechanical properties of PC/ABS blends

The morphology and the mechanical properties of polycarbonate (PC) blends with different acrylonitrile–butadiene–styrene (ABS) materials were investigated. PC/ABS blends based on a mass-made ABS with 16% rubber and large (0.5–1μm) rubber particles are compared to blends based on an emulsion-made ABS with 50% rubber and small, monodisperse (0.12 μm) rubber particles over the full range of blend compositions. The blends with the bulk ABS showed excellent impact strength for most compositions, and those containing 50 and 70% PC exhibited ductile to brittle transition temperatures below that of PC. The blends with the emulsion ABS showed excellent toughness in sharp notch Izod impact tests at room temperature and in standard notch Izod impact tests at low temperatures near the T_g of the rubber. By melt blending the various ABS materials with a styrene–acrylonitrile (SAN 25) copolymer, materials with lower rubber concentrations were obtained. These materials were used in blends with PC to make comparisons at constant rubber concentration of 5, 10, and 15%. The results of this investigation show that brittle ABS materials can produce tough PC–ABS blends. It is apparent that small rubber particles toughen PC–ABS blends at lower rubber concentrations and at lower temperatures than is possible with large rubber particles. However, additional work is needed to understand the nature of toughening in these PC–ABS blends with different rubber phase morphologies. It is of particular interest to understand the exceptional ductility of some of the blends at low temperatures. © 1994 John Wiley & Sons, Inc.     

螺杆组合及加料方式对PC/ABS力学性能的影响

研究了不同螺杆组合及加料方式对聚碳酸酯(PC)/丙烯腈-丁二烯-苯乙烯三元共聚物(ABS)合金挤出工艺和材料力学性能的影响,并设计了一种适合于PC/ABS合金加工的螺杆组合方式.结果表明:适当的螺杆组合和加料方式可改善PC/ABS的挤出工艺,提高材料的力学性能;PC/ABS合金的拉伸强度和弯曲强度分别由原来的56.43...     

ABS树脂中胶含量对PC/ABS合金微观结构的影响

本实验采用胶含量为60%的ABS接枝粉料与SAN树脂以不同比例进行共混,制备了胶含量范围为10%～55%的ABS树脂。将胶含量不同的ABS树脂与PC以30/70、50/50、70/30的比例利用熔融共混技术,制备了组成不同的PC/ABS共混物。利用SEM电镜观察了PC/ABS合金的微观结构。研究表明,ABS树脂含量为30%时,在合金中形成分散相;ABS树脂含量为70%时,形成连续相;ABS树脂含量为50%时与PC形成双连续相结构。在三种结构中,ABS树脂胶含量的增加都使合金的相形态变得更精细。     

相容剂对PC/ABS共混物性能的影响

本文分别研究了马来酸酐接枝ABS(ABS-g-MAH)与甲基丙烯酸甲酯/丁二烯/苯乙烯共聚物(MBS)作为相容剂对PC/ABS共混体系相容性、力学性能、形态结构的影响.研究结果表明:当相容剂MBS加入PC/ABS共混体系中后,不仅能够显著改善PC/ABS共混物的相容性,明显降低分散相的粒径,而且能够使PC/ABS共混物在保持较高的拉伸强度的同时,大幅度地提高共混物的缺口冲击强度和断裂伸长率;而相容剂ABS-g-MAH的加入对共混体系的缺口冲击强度的改善不明显,但其断裂伸长率增幅较大.     

注塑工艺对哑光PC/ABS光泽度的影响

研究了注塑工艺对哑光PC/ABS光泽度的影响。皮纹面的光泽度与材料复制模具的能力有关。注塑温度和模具温度升高,材料流动性提高,复制模具的能力提高,获得低光泽度。提高射胶速率和压力也会降低光泽度。光泽度随着保压压力的提高及保压时间的延长而降低。     

相容剂对PC/ABS合金力学性能的影响

研究了两种自制相容剂G1(苯乙烯/马来酸酐共聚物)和G2(改性马来酸酐接枝ABS)对PC/ABS合金力学性能(如缺口冲击强度、拉伸强度、伸长率和熔体流动速率)的影响。结果表明,两种相容剂都可有效提高PC/ABS合金的相容性,G1和G2的最佳加入量分别为3%和6%;相容剂的加入能够明显提高PC/ABS合金的冲击强度,增加体系粘度,降低熔体流动速率。     

相容剂对PC/ABS合金性能的影响

研究了自制的两种相容剂对PC／ABS合金的力学性能、应力开裂性能和熔体流动速率的影响,并用SEM研究了共混体系的相容性。结果表明,相容剂A[(苯乙烯／马来酸酐）共聚物]和相容剂B（ABS接枝共聚物）,均可提高共混体系中两组分的相容性。A、B的最佳用量分别为2％和5％。     

有机改性蒙脱土对无卤阻燃PC/ABS合金的影响

研究不同有机改性剂对蒙脱土(MMT)的层间距和热稳定性的影响,以及有机蒙脱土复配磷酸酯阻燃剂对聚碳酸酯/丙烯腈-丁二烯-苯乙烯共聚物(PC/ABS)合金的热稳定性和阻燃性能的影响。结果表明,有机改性剂使蒙脱土的层间距变大,热稳定性能满足加工要求。有机改性蒙脱土在基体中的分散性变好,形成插层结构。氮气氛围下,蒙脱土会促进合金的降解,但不影响最终残炭含量。双酚A(二苯基磷酸酯)(BDP)改性蒙脱土使PC/ABS(80/20)合金的第二个热释放峰值分别降为PC/ABS的66%和PC/ABS/FR16的76%。     

ABS／PA6挑战PC／ABS

据“Plastics Technology”,2002-09-02报道:BASF美国公司采用新型相容剂制备的ABS/PA6共混物系列新产品Terblendn适于替代目前汽车工业、娱乐用品、电子部件和家用电器用的ABS、PC/ABS、PC/PBT和ABS/PBT共混物。据称Terblend N系列产品有非常平衡的韧性和刚性,良好的加工性,极好的表面外观和手感,注塑产品性能(包括光泽)重复性好。不填充牌号(密度1.07g/cm~3)适于做汽车内饰件(仪表台、手套箱、气囊罩)和在外部镜     

Surfactant properties of low molecular weight phospholipids

Surface tensions, critical micelle concentrations (CMCs), contact angles on hydrophobic polyethylene, and foaming characteristics of phosphatidic acids, phosphatidylcholines, phosphatidylethanolamines, and phosphatidylglycerols were measured to determine their suitability as substitutes for traditional surfactants. These phospholipids have fatty acid chains of 5 to 12 carbon atoms, a range over which they are soluble at room temperature. Their surface tensions decrease with increasing concentrations until their CMCs are reached, above which their plateau surface tensions are as low as 21 mN/m, indicating excellent surface activities. In general, plateau surface tensions decrease with increasing chain length within each phospholipid type. The classical relationship for In CMC vs. chain length is followed with slopes typical of anionic surfactants for phosphatidic acids and phosphatidylglycerols and resembling zwitterionic surfactants for phosphatidylcholines and phosphatidylethanolamines, consistent with the charge on the hydrophilic group. The wetting capabilities of aqueous solutions on polyethylene are good and foam heights and stabilities are high, the latter two properties being comparable to traditional anionic (sodium dodecylsulfate) and nonionic (octylphenol polyethoxylate) surfactants. Some anomalies are observed regarding the effect of chain length on wetting and foaming, probably due to the depletion effect. Many phospholipids slowly degrade in aqueous solution. We conclude that short-chain phospholipids exhibit excellent surfactant properties and may be useful in many applications.     

ABS树脂中胶含量对PC/ABS合金性能及微观结构的影响

采用胶含量(质量分数,下同)为60％的丙烯腈-丁二烯-苯乙烯接枝共聚物(ABS)接枝粉料与苯乙烯-丙烯腈共聚物(SAN)以不同比例进行共混,制备了胶含量范围为10％～55％的ABS树脂.将胶含量不同的ABS树脂与聚碳酸酯(PC)以30/70、50/50、70/30的质量比利用熔融共混技术,制备了组成不同的PC/ABS共混物,考察了ABS树脂胶含量对不同组成的PC/ABS合金性能的影响.研究结果表明:随着ABS树脂中胶含量的增加,ABS树脂的冲击强度不断提高,屈服强度、模量及熔体流动速率逐渐降低.随着PC/ABS合金中ABS胶含量的增加,合金的冲击强度显著提高,ABS树脂中胶含量大于30％以后,合金的冲击强度变化不大,且3种组成的PC/ABS合金的冲击强度相差不大.合金的屈服强度、模量及熔体流动速率却随着ABS中胶含量的增加不断降低,其中组成为30/70的PC/ABS合金最低.利用扫描电镜观察了PC/ABS组成为70/30合金的微观结构,研究表明,ABS树脂形成连续相,PC为分散相,随ABS树脂胶含量的增加,合金的相形态变得更精细.     

高性能PC／ABS合金的制备及性能研究

为改善PC／ABS合金的耐低温、耐热及成型加工等性能,通过PC、AS及高胶粉的复合,考察了AS含量对合金各项性能的影响,并制备了具有耐低温、高热变形温度、高流动性、综合性能优异的PC／ABS合金。     

TPP和MBS对PC/ABS合金性能的影响

研究了磷系阻燃剂磷酸三苯酯(TPP)、增容剂甲基丙烯酸甲酯丁二烯苯乙烯(MBS)对聚碳酸酯(PC)/丙烯腈丁二烯苯乙烯共聚物(ABS)合金热稳定性、阻燃性能和力学性能的影响。结果表明,当加入16.7 % TPP(质量分数,下同)时,合金的UL 94测试可以达到 V-0级,极限氧指数也有了极大的提高;经MBS增容后,合金阻燃等级降低,极限氧指数较未增容合金提高0.5 %左右;加入TPP能减缓PC/ABS合金的降解,提高合金热稳定性,增加最终残炭率,但MBS的加入在一定程度上降低了合金的热稳定性。     

PC/ABS共混体系的研究进展

综述了PC/ABS共混体系相结构的分析结果、增容技术以及影响PC/ABS合金性能的主要因素。     

高效阻燃PC/ABS多元合金的相容性和性能研究

本文研究了阻燃PC/ABS多元合金的配方及制备工艺,采用高效阻燃体系和多元增容措施,制得了具有优异阻燃性能和冲击韧性的防火级PC/ABS合金。测试结果表明,采用丙烯酸酯共聚物、PS-g-MAH和SMA多元增容,加以高效复合阻燃剂,所制备的PC/ABS合金的冲击强度可达30kJ/m2,阻燃性能达到UL-94V0级,具有优良的综合性能。     

Recycling of ABS and ABS/PC blends

The aim of this work within the framework of mechanical recycling of polymers is upgrading recycled engineering plastics by means of a blending technique. Four different plastics from dismantled Volvo cars have been investigated. They are poly(acrylonitrile‐butadiene‐styrene) (ABS) and ABS‐polycarbonate (ABS/PC) as major components and poly(methyl methacrylate) (PMMA) and polyamide (PA) as minor components. Blending recycled ABS and PC/ABS (70/30) with a small amount of methyl methacrylate‐butadiene‐styrene core‐shell impact modifiers gives the mixture better impact properties than any of its individual components. Some 10% of PMMA from tail light housings can follow the PC/ABS blends made. The property profile will rather be improved. However, PA is an incompatible component that should be sorted out from the mixture. Antioxidants and metal deactivators do not help the recyclates show better mechanical properties. Two toughness measurements, Charpy impact strength and J‐integral method, show complimentary results for such blends. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 510–515, 1999     

分子量分布对低密度聚乙烯光氧老化特性的影响

采用衰减全反射红外光谱技术（ATR-FTIR）、热重分析法（TG）、凝胶渗透色谱（GPC）、扫描电子显微镜（SEM）和力学试验比较研究了不同分子量分布指数低密度聚乙烯（LDPE）的光氧老化特性,分析了分子量分布对LDPE化学结构、热稳定性、平均分子量、表面微观形貌和力学性能的影响规律。结果表明分子量分布越宽,LDPE不饱和度增长越剧烈,支化作用增长越显著;分子量分布越窄,羰基指数增长越快;分子量分布对于分子结构的断链行为并无影响。分子量分布指数越大,LDPE起始热分解温度和失重5%对应温度下降更快,热稳定性更容易变差,平均分子量下降更多,表面微观形貌老化现象越严重;弯曲强度和冲击强度受影响更显著,指数为6.0的LDPE老化24 d冲击强度就已丧失。分析认为,分子量越大、分布越窄表明分子链越长、短分子链越少,与氧接触而产生自由基的概率也越小,因此聚乙烯分子量分布越宽,材料越容易老化。     

PC及PC/ABS合金的增韧研究

研究了增韧剂SWR-7A对PC及PC／ABS增韧效果。比较了增韧剂SWR-7A与美国增韧剂GE-338及国内外其它增韧剂的增韧效果。研究表明，加入SWR-7A在提高PC及PC／ABS共混体系的冲击强度的同时，拉伸强度、弯曲强度及弯曲模量降低较少，达到了优化材料性能的目的，SWR-7A是一种理想的增韧剂。