聚对苯二甲酸丙二酯的热降解性能研究

用热重分析和热重红外联用分析以及黏度降研究了聚对苯二甲酸丙二酯(PTT)的热降解性能,并且与聚对苯二甲酸乙二酯(PET)、聚对苯二甲酸丁二酯(PBT)进行了比较。结果表明,PET的热稳定性比PTT及PBT好,而PTT和PBT的热稳定性相近。PTT中加入抗氧剂能提高PTT的热氧稳定性能。     

PTT复合材料力学性能研究进展

介绍了聚对苯二甲酸丙二醇酯(PTT)的结构特征、生产研究现状、有关的性能优势及其发展前景.给出了成核剂、增容共混物对PTT结晶性能的影响,以及聚丙烯(PP)、玻璃纤维(GF)、聚萘二甲酸乙二醇酯(PEN)短纤维、丙烯腈-丁二烯-苯乙烯(ABS)分别与PTT增容共混后力学性能的变化.可以看出,GF对PTT力学性能的提高很显著,能同时增韧增强,加入成核剂、增韧剂和PBT后进一步提高其部分力学性能,且改善了加工性能.PTT/ABS-g-MAH力学性能增加幅度比GF/PTT还要大,加入玻纤后性能进一步增强.     

高特性粘度聚酯的研究—化学增粘法

合成了对聚酯树酯端基具有活性的扩链剂BOZ,研究了对聚对苯二甲酸乙二酯(PET)和聚对苯二甲酸丁二酯(PBT)的扩链反应过程,扩链反应时间和扩链剂用量等对特性粘度的影响。实验结果表明:合成的扩链剂对PET和PBT能起扩链增粘作用,使分子量提高。可得到特性粘度0.98的PET树脂和特性粘度1.62的PBT树脂。     

螺杆组合方式对GF增强PET/PBT共混物性能的影响

采用同向平行双螺杆挤出机制备玻璃纤维(GF)增强聚对苯二甲酸乙二酯(PET)/聚对苯二甲酸丁二酯(PBT)共混物。在固定组分配比及共混挤出工艺条件的基础上,研究了螺杆不同组合方式,即剪切块数量及排布方式对挤出工艺及GF分散程度和长度的影响,进而对GF增强PET/PBT共混物性能造成的影响,设计出了一种适合GF增强PET/PBT共混物挤出生产的螺杆组合方式,采用该螺杆组合方式制备GF增强PET/PBT共混物,不但挤出工艺稳定可靠,而且产品性能实现最优化。     

高特性粘度(分子量)聚酯的研究——化学增粘法[摘]

目前工业上用熔融缩聚法生产得到的聚对苯二甲酸乙二酯(PET)和对苯二甲酸丁二酯(PBT)树脂切片的特性粘度分别为0.7和1左右。要制得高特性粘度树脂必须后加固相缩聚来生产。本工作合成了对聚酯树脂端基具有活性的扩链剂,研究了对PET和PBT的扩链反应过程,扩链反应时间和扩链剂用量等对特性粘度的影响。实验结果表明:合成的扩链剂对PET和PBT能起扩链增粘作用,使分子量提高,可得到特性粘度0.98的PET和特性粘度1.62的PBT树脂。     

聚对苯二甲酸乙二酯合金的研究进展

概述了近些年聚对苯二甲酸乙二酯(PET)的热塑性聚酯合金,如PET与聚烯烃(PO)、聚碳酸酯(PC)、聚对苯二甲酸丙二酯(PTT)、聚对苯二甲酸丁二酯(PBT)等的研究进展。叙述包括PET,PO,PC,PTT,PBT纯树脂和相应合金的性能优缺点以及近期关于此类合金相容性、酯交换反应、结晶性能和力学性能的研究进展,并分析了研究过程中存在的问题。     

PTT工程塑料的开发和应用

介绍聚对苯二甲酸丙二酯(PTT)基础树脂的合成工艺路线及其主要原料1，3-丙二醇(PDO)的生产工艺路线。阐述了PTT树脂的发展概况和现状，国际主要生产商的发展动向，国内PTT树脂和原料PDO的开发状况及建设规划。比较了PTT、PET、PBT、PA66和PC的纯树脂品级和玻璃纤维增强品级的性能，概述了PTT的开发和应用状况，介绍了商业化系列PTT产品的牌号和性能，并展望了PTT的市场前景。     

GF增强PBT/PET合金的性能和外观

在质量分数30%玻璃纤维(GF)增强聚对苯二甲酸丁二酯(PBT)的基础上,通过引入不同含量的聚对苯二甲酸乙二酯(PET)组分制备了不同PBT/PET比例的合金。系统研究了PET含量对合金的傅立叶变换红外光谱(FTIR)、熔融结晶行为、力学性能、流动性能及外观的影响。实验结果显示:PET引入后,合金的FTIR谱图中出现了PET特征吸收峰(1 341cm-1);由于发生了部分酯交换反应,合金中PBT和PET的结晶能力减弱;PET的加入提高了GF增强PBT的力学性能,拉伸强度和弯曲强度分别能够提高10.1%和8.9%;相较于GF增强PBT,GF增强PBT/PET合金的流动性有所提高;同时,GF增强PBT/PET合金注塑制品的外观得到显著改善,样品表面浮纤面积占比由GF增强PBT的7.6%降低至GF增强PBT/PET合金(PET质量分数为40%)的0.4%。当PET质量分数为20%～35%时,所得PBT/PET合金同时具备优异的力学性能和良好的外观。     

玻璃纤维增强PC/PBT共混体系力学性能的研究

采用增容剂对玻璃纤维(GF)增强聚碳酸酯(PC)聚/对苯二甲酸丁二酯(PBT)共混体系进行改性,研究了不同成分组成对GF增强PC/PBT材料力学性能的影响,并用扫描电子显微镜观察了不同共混体系的形态结构。结果表明,GF可以提高共混体系的力学性能,当GF质量分数为28%时,共混体系的综合性能较好。     

PTT/PBT共混纤维的性能研究

利用聚对苯二甲酸-1,3-丙二酯(PTT)和聚对苯二甲酸丁二酯(PBT)良好的相容性,开发了PTT/ PBT共混纤维。通过对共混纤维的力学、回弹及染色等性能测试发现,PTT组分的存在明显改善了共混纤维的拉伸性能,而共混纤维的强度相对纯组分纤维略差;当PTT质量分数达到50%后,共混纤维的回弹性优于纯PBT纤维,且在相同拉伸倍数下,PTT的存在降低了共混纤维的沸水收缩率;共混纤维在常压下用分散蓝染色的上染率比纯组分纤维高,当PTT/PBT质量比为50/50时,上染率最高。     

The hydrolytic stability of glass fiber reinforced poly(butylene terephthalate), poly(ethylene terephthalate) and polycarbonate

The hydrolytic stability of glass fiber reinforced poly(butylene terephthalate) (PBT), poly(ethylene terephthalate) (PET) and polycarbonate (PC) was studied. The activation energies in kcal/mole for hydrolysis are 26 for PBT and 23 for PET. Both PBT and PET contain 30 percent glass fiber reinforcement. The hydrolysis rates for a series of experimental PC's containing 10, 30 and 40 percent glass were obtained from GPC data. These increase with glass concentration but are lower than that of the unreinforced PC. Melt flow rate changes are a good measure of the hydrolytic degradation of PET. However, in the time scale of these experiments, the tensile properties of glass reinforced PBT and PC do not correlate well with M?_w changes, unlike unreinforced PBT and PC polymers. Consequently, to compare these three glass fiber reinforced polymers, estimates of failure time must be based on changes in tensile strength rather than melt flow rate.     

Study of poly(trimethylene terephthalate) as an engineering thermoplastics material

Poly(trimethylene terephthalate) (PTT) was systematically studied as an engineering thermoplastics material. Crystallization rates, crystalline degrees, and mechanical properties of two commercial PTT polymers and one glass fiber–reinforced PTT compound were investigated and compared with those of poly(butylene terephthalate) (PBT). PTT raw polymers have crystallization temperature (T_c) values around 152°C, and their kneaded polymers show T_c values of about 177°C, about 15°C lower than the values of PBT polymers used in this study. From the exothermic heat values of DSC measurements, both PTT and PBT show the crystalline degree order greater than 30%. Injection‐molded PTT specimens and PBT specimens exhibit crystalline degrees from 18 to 32% and 23.8 to 30%, respectively. PTT polymers show higher tensile and flexural strengths, but lower impact strengths and elongations than those of PBT polymers. The low elongation behavior of PTT does not change with the intrinsic viscosity and the molder temperature. PTT‐GF30 promotes better mechanical properties than those of PBT‐GF30, close to those of PET‐GF30. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1657–1666, 2004     

封端异氰酸酯对低粘度PBT改性的研究

以封端异氰酸酯(BMDI)作低粘度聚对苯二甲酸丁二酯(PBT)的改性剂,考察改性前后PBT的特性粘度、端基含量、力学性能的变化。结果表明,改性后PBT的特性粘度从0．82dL／g提高到1．3dL／g以上;端羟基含量从84．2mmol／kg降至35．1mmol／kg;端羧基含量从31．3mmol／kg降至21mmol／kg;BMDI用量在理论用量之内时,PBT的力学性能得到明显提高,超过理论用量,由于产生凝胶其力学性能降低;随着BMDI用量的增加,玻纤增强低粘度PBT的力学性能也得到提高,基本达到玻纤增强正品PBT的性能指标。     

Reaction injection molding of mica reinforced polyurethane

Reaction injection molded polyurethanes are reinforced with inorganic materials to improve stiffness and structural integrity at elevated temperatures and to reduce the coefficient of thermal expansion. This work describes the reinforcement obtained with an experimental grade of mica designed to achieve low viscosity of mica suspensions in polyol. The effect of mica on properties is essentially identical to that of glass flake (i.e., improved stiffness at the cost of reduced impact strength). Compared to hammer milled glass fiber, mica and glass flakes yield more isotropic, albeit weaker, materials. The study of unreinforced polyurethane shows that mechanical properties (tensile and impact strength, flexural modulus) are approximately proportional to the square of foam density.     

玻纤增强PBT／AS合金相容性的研究

通过熔融共混法制备了玻纤增强聚对苯二甲酸丁二醇酯（PBT）／丙烯腈-苯乙烯共聚物（As）合金。研究了不同相容剂对合金力学性能的影响,结果表明,加入相容剂能很好的提高合金的力学性能,其中加入4％自制相容剂对合金力学性能的提高最为明显。DSC分析表明,相容剂的加入能降低PBT的熔点,提高两相相容性。     

玻纤增强PA66/PBT合金的相形态及力学性能研究

通过熔融共混法制备了玻纤增强聚己二胺己二酸(PA66)/聚对苯二甲酸丁二醇酯(PBT)合金,研究了自制相容剂对玻纤增强PA66/PBT合金力学性能及相形态的影响。DSC及SEM结果表明,加入5%自制容剂能有效增容PA66和PBT,减少分散相的相尺寸,使合金的力学性能特别是合金的冲击性能达到甚至超过玻纤增强PA66的力学性能,同时合金的吸水率随合金体系中PBT用量的增加而大幅降低。     

Preparation,structure, and properties of the PTT/SGF composites

Short glass fiber reinforced poly(trimethylene terephthalate) composites (PTT/SGF) were prepared by twin screw extruder. The structural feature and physical properties of these composites were studied by scanning electron microscope, differential scanning calorimetry, thermalgravimetric analyzer, capillary rheometer, universal tester, etc. The glass fiber was modified by the silane coupling agent before being blended with the polymer. The results suggest that there is strong interaction between SGF and PTT matrix, which leads to an increasing on the tensile strength, Young's modulus, impact strength and thermal stability of the composites with proper contents of SGF. Rheological behavior of the PTT/SGF composites melt is complicated, combining a dilate fluid at lower shear rate and a pseudo-plastic fluid at higher shear rate. The melt apparent viscosity of composites decreases with increasing SGF content because of the rigid fibers improving the flow of the melt. Moreover, the flow activation energy of the composites suggests that the melt with more SGF has lower sensitivity to the processing temperature. In conclusion, the composite with 10–20 wt% content of SGF has better properties. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers