HIPS-g-MA共聚物对HIPS/PC共混物相容性、形态和拉伸性能的影响

研究了 HIPS/ PC共混物的相容性及 HIPS- MA对 HIPS( 30 ) / PC( 70 )共混物的相容性、形态和拉伸性能的影响。DSC研究结果表明 ,HIPS/ PC共混物中 PS的玻璃化转变温度 ( Tg)不随组成而变化 ,而PC的 Tg 随其质量分数的降低逐渐向低温移动 ,说明 HIPS/ PC是部分相容体系。通过 DSC、扫描电镜形态观察和拉伸性能测试结果发现 ,当 HIPS- g- MA的含量低于 7.5 %时 ,共混物的相容性改善不明显 ,当其含量达到 7.5 %时 ,对共混物有明显的乳化作用 ,说明饱和的界面浓度在 7.5 %左右。HIPS- g- MA接枝共聚物在 HIPS( 30 ) / PC( 70 )共混物中的增容作用可能是酯交换反应原位生成的嵌段共聚物所致

Morphology, crystallization behaviors, and mechanical properties of PA1010/HIPS and PA1010/HIPS-g-MA blends

The binary blends of polyamide 1010 (PA1010) with the high-impact polystyrene (HIPS)/maleic anhydride (MA) graft copolymer (HIPS-g-MA) and with HIPS were prepared using a wide composition range. Different blend morphologies were observed by scanning electron microscopy according to the nature and content of PA1010 used. Compared with the PA1010/HIPS binary blends, the domain sizes of dispersed-phase particles in PA1010/HIPS-g-MA blends were much smaller than that in PA1010/HIPS blends at the same compositions. It was found that the tensile properties of PA1010/HIPS-g-MA blends were obviously better than that of PA 1010/HIPS blends. Wide-angle xray diffraction analyses were performed to confirm that the number of hydrogen bonds in the PA1010 phase decreased in the blends of PA1010/HIPS-g-MA. These behaviors could be attributed to the chemical interactions between the two components and good dispersion in PA1010/HIPS-g-MA blends.

Morphologies and physical properties of PA1010/HIPS/HIPS-g-MA ternary blends

The effect of the content of a copolymer consisting of high impact polystyrene grafted with maleic anhydride (HIPS-g-MA) on morphological and mechanical properties of PA1010/HIPS blends has been studied. Blend morphologies were controlled by adding HIPS-g-MA during melt processing, thus the dispersion of the HIPS phase and interfacial adhesion between the domains and matrices in these blends were changed obviously. The weight fractions of HIPS-g-MA in the blends increased from 2.5 to 20, then much finer dispersions of discrete HIPS phase with average domain sizes decreased from 6.1 to 0.1 mu m were obtained. It was found that a compatibilizer, a graft copolymer of HIPS-g-MA and PA1010 was synthesized in situ during the melt mixing of the blends. The mechanical properties of compatibilized blends were obviously better than those of uncompatibilized PA1010/HIPS blends. These behaviors could be attributed to the chemical interactions between the two components of PA1010 and HIPS-g-MA and good dispersion in PA1010/HIPS/HIPS-g-MA blends. Evidence of reactions in the blends was seen in the morphology and mechanical behaviour of the solid. The blend containing 5 wt % HIPS-g-MA component exhibited outstanding toughness. (C) 1999 Kluwer Academic Publishers.

Preparation of the HIPS/MA graft copolymer and its compatibilization in PA6/HIPS blends

The graft copolymer of high impact polystyrene (HIPS) grafted with malice anhydride (MA) (HIPS-g-MA) was prepared with melt mixing in the presence of a free-radical initiator. The grafting reaction was confirmed by IR analyses and the amount of MA grafted on HIPS was evaluated by a titration method. 1-5 wt% of MA can be grafted on HIPS. HIPS-g-MA is miscible with HIPS. Its anhydride group can react with the PA6 during melt mixing the two components. The compatibility of HIPS-g-MA in the HIPS/PA6 blends was evident. Evidence of reactions in the blends was confirmed in the morphology and mechanical properties of the blends. A significant reduction in domain size was observed because of the compatibilization of HIPS-g-MA in the blends of HIPS and PA6. The tensile mechanical properties of the prepared blends were investigated and the fracture surfaces of the blends were examined by means of the scanning electron microscope (SEM). The improved adhesion in a 16%HIPS/75%PA6 blend with 9%HIPS-g-MA copolymer was detected. The morphology of fibrillar ligaments formed by PA6 connecting HIPS particles was observed.

Preparation of the HIPS/MA graft copolymer and its compatibilization in HIPS/PA1010 blends

The graft copolymer of high-impact polystyrene (HIPS) grafted with maleic anhydride (MA) (HIPS-g-MA) was prepared with melt mixing in the presence of a free-radical initiator. The grafting reaction was confirmed by infrared analyses, and the amount of MA grafted on HIPS was evaluated by a titration method. 1-5% of MA can be grafted on HIPS. HIPS-g-MA is miscible with HIPS. Its anhydride group can react with polyamide 1010 (PA1010) during melt mixing of the two components. The compatibility of HIPS-g-MA. in the HIPS/PA1010 blends was evident. Evidence of reactions in the blends was confirmed in the morphology and mechanical behavior of the blends. A significant reduction in domain size was observed because of the compatibilization of HIPS-g-MA in the blends of HIPS and PA1010. The tensile mechanical properties of the prepared blends were investigated, and the fracture surfaces of the blends were examined by means of the scanning electron microscope. The improved adhesion in a 15% HIPS/75% PA1010 blend with 10% HIPS-g-MA copolymer was detected. The morphology of fibrillar ligaments formed by PA1010 connecting HIPS particles was observed. (C) 1999 John Wiley & Sons, Inc.

Morphology and thermal and mechanical properties of PBT/HIPS and PBT/HIPS-g-GMA blends

The modification of high-impact polystyrene (HIPS) was accomplished by melt-grafting glycidyl methacrylate (GMA) on its molecular chains. Fourier transform infrared spectroscopy and electron spectroscopy for chemical analysis were used to characterize the formation of HIPS-g-GMA copolymers. The content of GMA in HIPS-g-GMA copolymer was determined by using the titration method. The effect of the concentrations of GMA and dicumyl peroxide on the degree of grafting was studied. A total of 1.9% of GMA can be grafted on HIPS. HIPS-g-GNU was used to prepare binary blends with poly(buthylene terephthalate) (PBT), and the evidence of reactions between the grafting copolymer and PBT in the blends was confirmed by scanning electron microscopy (SEM), dynamic mechanical analysis, and its mechanical properties. The SEM result showed that the domain size in PBT/HIPS-g-GMA blends was reduced significantly compared with that in PBT/HIPS blends; moreover, the improved strength was measured in PBT/HIPS-g-GMA blends and results from good interfacial adhesion. The reaction between ester groups of PBT and epoxy groups of HIPS-g-GMA can depress crystallinity and the crystal perfection of PBT.

Effect of compatibilization on the properties of HIPS/PA1010 blends

Blends consisting of high-impact polystyrene (HIPS) as the matrix and polyamide 1010 (PA1010) as the dispersed phase were prepared by mixing. The grafting copolymers of HIPS and maleic anhydride (MA), the compatibilizer precursors of the blends, were synthesized. The contents of the IMA in the grafting copolymers are 4.7 wt % and 1.6 wt %, and were assigned as HAM and LMA, respectively. Different blend morphologies were observed by scanning electron microscopy (SEM); the domain size of the PA1010 dispersed phase in the HIPS matrix of compatibilized blends decreased comparing with that of uncompatibilized blends. For the blend with 25 wt % HIPS-g-MA component, the T-c of PA1010 shifts towards lower temperature, from 178 to 83 degrees C. It is found that HIPS-g-MA used as the third component has profound effect on the mechanical properties of the resulting blends. This behavior has been attributed to the chemical reaction taking place in situ during the mixing between the two components of PA1010 and HIPS-g-MA. (C) 2000 John Wiley & Sons, Inc.

The compatibility and morphology of HIPS/PC and HIPS-g-GMA/PC blends

The compatibility and morphology of HIPS/PC and HIPS-g-GMA/PC blends were studied. The compatibility and morphology of HIPS/PC blends were characterized by DSC and SEM, respectively. The result of DSC shows that T-g of PS doesn't change with the blend composition, and T-g of PC decreases with the increase in weight fraction of HIPS, which indicates that the PC/HIPS blend is a partially miscible system. Results of SEM indicate that the decrease in T-g of PC results from PS interpenetrating into the phase of PC, and no change in T-g of PS results from PC not interpenetrating into the phase of PS. The copolymer of HIPS-g-GMA was prepared by reactive grafting method. The IR spectrum shows that GMA is grafted on the chain of HIPS. The compatibility and morphology of HIPS-gGMA (35)/PC (65) were studied by DSC and SEM. PC (65)/HEPS-g-GMA (35) blend exhibits reduced size of disperse phase, enhanced interface adhesion and lower T-g of PC phase as compared with the PC(65)/HIPS(35) blend. It implies that HIPS-g-GMA is an effective compatibilizer of the HIPS/PC blend.

Blends of polyamide 1010 with ungrafted and maleic anhydride grafted high impact polystyrene

The crystallization, dynamic mechanical properties, tensile properties and morphology features of polyamidel 1010(PA1010) blends with the high impact polystyrere (HIPS) and maleic anhydride (MA) grafted HIPS(HIPS-g-MA) were examined at a wide composition range. By comparison the PA1010/HIPS-g-MA and PA1010/HIPS binary blends, it was found that the size of the domains of HIPS-g-MA was much smaller than that of HIPS at the same compositions. It was found that the mechanical properties of PA1010/HIPS-g-MA blends were obviously higher than those of PA1010/HIPS blends. When the content of PA1010 is more than 50wt% in the blends, the crystallization temperatures, T-cs, of PA1010 increase with increasing the content of HIPS-g-MA. On the other hand, when the content of PA1010 in the blends is less than 35wt% the fraction crystallization is observed. The same result is not obtained for the blends of PA1010/HIPS. These behaviors could be attributed to the chemical interactions between the two components and good dispersion in PA1010/HIPS-g-MA blends.

Blends of polyamide1010 with unmodified and maleic-anhydride-grafted high-impact polystyrene

The crystallization behaviors, dynamic mechanical properties, tensile, and morphology features of polyamide1010 (PA1010) blends with the high-impact polystyrene (HIPS) were examined at a wide composition range. Both unmodified and maleicanhydride-(MA)-grafted HIPS (HIPS-g-MA) were used. It was found that the domain size of HIPS-g-MA was much smaller than that of HIPS at the same compositions in the blends. The mechanical performances of PA1010-HIPS-g-MA blends were enhanced much more than that of PA1010-HIPS blends. The crystallization temperature of PA1010 shifted towards higher temperature as HIPS-g-MA increased from 20 to 50% in the blends. For the blends with a dispersed PA phase (less than or equal to 35 wt %), the T-c of PA1010 shifted towards lower temperature, from 178 to 83 degrees C. An additional transition was detected at a temperature located between the T-g's of PA1010 and PS. It was associated with the interphase relaxation peak. Its intensity increased with increasing content of PA1010, and the maximum occurred at the composition of PA1010-HIPS-g-MA 80/20. (C) 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 857-865, 1999.

尼龙1010分别与未接枝和接枝马来酸酐的高抗冲聚苯乙烯的共混体系研究

研究了尼龙1010(PA1010)与高抗冲聚苯乙烯(HIPS)及马来酸酐官能化的HIPS(HIPS-g-MA)间的相互作用，利用DSC,DMA,SEM及拉伸测试等方法研究了不同组成比的共混物PA1010/HIPS与PA1010/HIPS-g-MA的结晶、玻璃化转变、形态及力学性能．结果表明HIPS与PA1010虽然结构相差甚远，但两者之间仍存在着一定的相互作用；而HIPS-s-MA可使PA1010的低温熔融峰变小，当HIPS-g-MA的含量≤50%时，随着其含量的增加，共混物中PA1010的结晶温度升高；当含量＞50%时，PA1010发生分级结晶行为，其结晶温度由原来的178℃降至83℃，同时HIPS-g-MA与PA1010间的相互作用变大，DMA谱上有明显的新的松驰峰．PA1010/HIPS-g-MA共混体系的拉伸性能要优于相同组成的PA1010/HIPS体系．以上现象主要是...

PBT/HIPS枘混体系的结构与性能及生物隆解聚合物结晶性能的研究

以过氧化二异丙苯(DCP)为引发剂，甲基丙烯酸缩水甘油醋(GMA)为活性单体对HIPS进行熔融接枝，制得了功能化的高抗冲苯乙烯(HIPS－g－GMA）。比较HIPS－g－GMA和纯的HIPS的红外谱图，可以看到在HIPS－g－GMA的谱图上出现了一个新的吸收峰，即1730cm~(-1)处的C=O的伸缩振动吸收峰，它为接枝的GMA中的醋基基团的特征峰，因此可以确定GMA己经接枝到HIPS上。能谱分析也提供了相似的结论。同时研究了单体浓度和DCP用量对产物接枝率的影响。用化学滴定方法测定了接枝物的接枝率。随着GMA量的增加，接枝率也随之增加，当GMA用量超过14％时，接枝率趋于平缓；接枝率随DCP量增加而增加。采用DSC、SEM, WAXD, DMA及力学性能等方法和手段研究PBTIHIPS和PBT/HIPS-g-GMA二元共混体系的结晶、形态结构、动态力学性能及力学性能随组成的变化。当PBT为分散相，在增容体系中的PBT出现了分级结晶现象，结晶温度降低，这是由于分散相更为精细的结果。DMA结果表明，在PBTIHIP S-g-GMA体系中由于发生了化学反应，有接枝共聚物生成，体系中两个聚合物的Tg松弛均出现了较明显的降低，增容后体系的力学性能有显著提高。采用DSC, SEM, DMA及力学性能等方法和手段研究PBT/HIPS/HIPS-g-GMA三元共混体系的结构与性能。结果表明PBT无论是分散相还是连续相，HIPS-g-GMA的作用表现为：（1）对PBTIHIPS体系的熔融和结晶行为产生了明显的影响，使PBT的结晶速率变慢，结晶度降低，结晶尺寸分布变宽，结晶完善性变差；（2）改善了共混体系的相容性。未增容体系的形态结构为锐型界面，分散相粒子同基材相连接处清晰缝隙表明两组分间界面粘接很差，为典型的不相容两相形态结构；而加入功能化接枝物的体系的分散相粒子明显变小且分布均匀，甚至难以分辨两相结构的界面；（3）提高了体系的力学性能。在多官能团单体存在下，辐照对PBTIHIPS产生影响。（1）对共混体系的熔融和结晶行为产生影响，使共混体系中的PBT的熔点降低，熔程变宽，结品度下降，结晶速率变慢，结晶尺寸分布变宽，结晶完善性变差；（2）辐射引发多官能团单体反应，使体系的两个Tg松弛发生内移，表明体系的相容性得到改善；（3）当PBT为连续相时，辐射引发的多官能团单体反应对体系的形态结构影响不如化学增溶剂HIPS-g-GMA的效果显著，含有TMPTA的体系的形态结构要好于TAIL o当PBT为分散相，体系的形态结构变化很大，分散相尺寸明显变下小，且分布均匀；（4）辐射改性能提高PBT为分散相的共混体系的力学性能。利用DSC研究了不同成核剂对生物降解聚合物PHBV的结晶性能的彩响。结果表明：（1)添加的成核剂均能影响PHBV的结晶和熔融行为，提高PHBV的结晶速率和使PHBV的结晶更加完美；（2）所有的成核剂均能降低PHBV的结晶自由能；（3）成核剂对PHBV的影响依次为BN, talc, Tb_2O_3和La_2O_3。