高抗冲PET/PC合金的相容性研究

以热塑性弹性体乙烯-1-辛烯共聚物(POE)或甲基丙烯酸缩水甘油酯(GMA)接枝POE(gPOE)作为改性剂,通过双螺杆反应挤出的方法制备聚对苯二甲酸乙二醇酯/聚碳酸酯(PET/PC)共混物。利用差示扫描(DSC)、动态热机械分析(DMA)、熔体质量流动速率(MFR)和扫描电子显微镜(SEM)等手段对PET/PC共混物的结晶性、相容性、加工性和相结构进行了表征。结果表明,gPOE添加量为15 phr时,共混物的缺口冲击强度为27.8 kJ/m2,是纯PET的6倍,断裂伸长率达到373%。相态研究显示共混物中大部分分散相粒子被拉伸变形,粒子周围基体凹凸不平,这是因为共混过程中PET的端羧基和gPOE的环氧基团之间可以发生反应,生成的接枝共聚物提高了组分之间的相容性,gPOE的加入同时解决了挤出过程中的出口膨胀现象,改善了加工性。     

马来酸酐接枝乙烯-辛烯共聚物对聚对苯二甲酸丁二醇酯的增韧作用

研究了马来酸酐接枝乙烯-辛烯共聚物(POE—g—MAH)和POE—g—MAH／聚丙烯(PP)共混物对聚对苯二甲酸丁二醇酯(PBT)的增韧作用。结果表明,POE—g—MAH／PP共混物对PBT的增韧效果优于POE—g—MAH的,POE—g—MAH和PP并用具有显著的协同增韧作用。扫描电镜照片表明,POE—g-MAH／PP共混物增韧PBT具有软壳-硬核结构。     

环氧化EPDM对PBT/LLDPE共混体系的微观形态及力学性能的影响研究

采用反应性熔融共混技术制备了聚对苯二甲酸丁二醇酯(PBT)/线型低密度聚乙烯(LLDPE)共混物,并采用环氧化三元乙丙橡胶(eEPDM)为增容剂改善PBT/LLDPE共混体系的相容性。使用红外光谱(FTIR)和扫描电子显微镜(SEM)等手段对共混物进行了分析和相形态观察,并测试了力学性能,研究了eEPDM对PBT/LLDPE共混体系形态结构和力学性能的影响。研究结果表明,熔融共混过程中eEPDM的环氧基团与PBT的端羧基发生化学反应,就地生成PBT-g-EPDM共聚物,该共聚物可对PBT/LLDPE共混物起到良好的增容作用。与PBT/LLDPE/EPDM共混体系相比,PBT/LLDPE/eEPDM共混物的相区尺寸更小,分布更窄,而且加入eEPDM在改善冲击强度方面比添加EPDM更有效。     

PBT与官能化POE共混过程中的增容反应研究

采用带流变槽的HAAKE流变仪研究了乙烯-辛烯共聚物（POE）和甲基丙烯酸缩水甘油酯接枝乙烯-辛烯共聚物（POE-g-GMA）与聚对苯二甲酸丁二醇酯（PBT）共混物的黏度随共混时间的变化过程，并对这两种共混物的断面形貌和力学性能进行对比分析。结果表明，由于POE-g-GMA能够与PBT发生原位增容反应，使得POE-g-GMA颗粒的粒径小、分散均匀，体系黏度随共混时间先长时间持续上升，然后保持不变，体系最终黏度也随着POE-g-GMA浓度升高而升高；然而在不发生反应的PBT／POE体系中，POE颗粒分散性差，颗粒粒径大，体系黏度受POE的浓度影响相对较小且随时间基本上保持不变。由于POE-g-GMA与PBT之间的增容反应使得PBT／POE-GMA的力学性能优于PBT／POE，并且冲击强度随POE-g-GMA浓度呈现两个阶段变化，即低于临界浓度时冲击强度缓慢升高，高于临界浓度时冲击强度快速升高。     

SEBS—g—MAH对PO／PBT共混物性能影响

利用双螺杆挤出机制备聚碳酸酯（Pc）／聚对苯二甲酸丁二醇酯（PBT）／-B来酸酐接枝氢化苯乙烯-丁二烯啕E乙烯共聚物（SEBS-g—MAH）的共混物。通过扫描电子显微镜（SEM）、平板流变仪研究了SEBS-g—MAH对PC／PBT共混物的机械性能、断面形态结构、动态力学行为的影响。结果表明：SEBS-g—MAH提高了PC／PBT共混物的相容性,随着SEBS-g—MAH用量的增加,共混物的缺口冲击强度和断裂伸长率上升,拉伸强度和弯曲强度下降。当SEBS—g-MAH质量分数为5％时共混物的综合性能最佳,同时,SEBS-g—MAH的加入,并未对PC／PBT共混物的成型加工性能产生不良影响。     

PBT/官能化聚烯烃弹性体共混体系的力学性能与相形态

考察了马来酸酐接枝乙烯-辛烯共聚物（POE-g-MAH）和乙烯-丙烯酸甲酯-甲基丙烯酸缩水甘油酯三元共聚物（E-MA-GMA）对聚对苯二甲酸丁二醇酯（PBT）的增韧作用。结果表明，未接枝的POE弹性体对PBT缺口冲击韧性的改善作用不大。两种官能化聚烯烃弹性体（E-MA-GMA、POE-g-MAH）对PBT具有显著的增韧作用。当弹性体用量分别达到8．5％和10％以后，共混物都各自出现明显的脆／韧转变现象。这意味着在达到同样的冲击韧性时，PBT／E—MA—GMA共混体系的拉伸强度损失较小。SEM显示，PBT／E—MA—GMA共混体系中分散相具有更细微的分散，有效地诱导PBT基体产生银纹和剪切屈服，消耗大量的冲击能。     

POE接枝MA增韧PBT的研究

用熔融接枝法制备的马来酸酐接枝乙烯-1-辛烯共聚物(POE-g-MA)对聚对苯二甲酸丁二醇酯(PBT)的增韧改性,研究了不同接枝率的POE-g-MA对PBT/POE-g-MA共混物力学性能、结构以及熔融结晶行为的影响。结果表明,POE接枝MA后可明显提高POE与PBT的相容性及PBT的冲击性能,但接枝率过高反而会影响界面黏结,使冲击性能降低。     

Friedel-Crafts烷基化反应原位增容SAN/POE研究

在熔融状态下,利用Friedel-Crafts烷基化反应原位增容苯乙烯-丙烯腈共聚物(SAN)/乙烯-辛烯共聚物(POE)共混物,考察了AlCl3对该共混物性能的影响。结果表明,对于SAN/POE(70/30,质量比)共混物,加入0.4%AlCl3时,共混物的拉伸强度提高了31%,断裂伸长率提高了123%;红外光谱分析表明,AlCl3可以引发SAN与POE发生Friedel-Crafts烷基化反应生成SAN-g-POE接枝物;旋转流变分析、热分析以及微观结构分析表明,由于增容体系中有SAN-g-POE接枝物生成,共混体系的表观黏度增加,热稳定性提高,分散均匀性提高。     

基本断裂功方法表征PP及弹性体增韧PP的冲击韧性

将基本断裂功(EWF)方法应用于聚丙烯(PP)、PP/(乙烯/丙烯/二烯)共聚物(EPDM)和PP/(乙烯/1-辛烯)共聚物(POE)共混体系的冲击韧性表征。结果表明,加入EPDM或POE后,共混物的比基本断裂功we和比塑性形变功βwp均有提高,说明弹性体的加入提高了材料抵抗裂纹扩展的能力和发生塑性形变的能力。含质量分数8%EPDM或POE的PP共混物的we和βwp高于含1%EPDM或POE的PP共混物。通过对试样冲击断面和应力发白区域的观察证实了EWF方法表征的结果。EWF方法为评价聚合物材料的断裂行为提供了更多的数据,是一种表征材料冲击韧性的极好的方法。     

PE-g-MAH增容PA 66/POE的形态与性能

使用马来酸酐接枝聚乙烯(PE-g-MAH)作为乙烯-辛烯共聚物(POE)增韧聚酰胺(PA)66的增容剂,研究了PE-g-MAH用量对PA 66/POE共混物的力学性能和形态影响。随着PE-g-MAH用量的增加 PA 66和POE的相容性显著改善,共混物中各组分的熔融峰温下降;共混物的缺口冲击强度显著提高,断裂伸长率成倍增大,韧性也有提高。当w(PE-g-MAH)为8%时,增容效果较好。     

PP/POE及PP/EPDM共混改性研究

以茂金属聚烯烃弹性体(POE,乙烯-辛烯共聚物)和三元乙丙橡胶(EPDM)作为聚丙烯(PP)的增韧剂,研究了PP/POE及PP/EPDM共混物的加工性能及力学性能。研究结果表明,POE在加工性、增韧改性等方面比EPDM更具有优势。借助扫描电子显微镜(SEM)进一步探讨了共混物的形态结构与性能的关系。     

POE与EPDM对聚丙烯增韧改性研究

以茂金属聚烯烃弹性体(POE,乙烯-辛烯共聚物)和传统三元乙丙胶(EPDM)作为聚丙烯(PP)的增韧剂,比较研究了PP/POE及PP/EPDM共混物的加工性能及力学性能。研究结果表明,POE在加工性、增韧改性等方面比EPDM更具有优势。扫描电子显微镜(SEM)进一步探讨了共混物的形态结构与性能的关系。     

Toughening modification of PBT/PC blends with PTW and POE

New toughened poly(butylene terephthalate) (PBT)/bisphenol A polycarbonate (PC) blends were obtained by melt blending with ethylene–butylacrylate–glycidyl methacrylate copolymer (PTW) and ethylene‐1‐octylene copolymer (POE) in a twin‐screw extruder. The mechanical properties of PBT/PC blends were investigated. The presence of PTW or POE could improve the mechanical properties except for the tensile strength and flexural properties of the PBT/PC blends. However, a combination use of PTW and POE had a strong synergistic effect, leading to remarkable increases in the impact strength, elongation at break, and Vicat temperature and some reduction of the tensile strength and flexural properties. The relationship between mechanical properties and morphology of the PBT/PC/PTW/POE blends was studied. The morphology was observed by scanning electron microscopy and the average diameter of dispersed phase was determined by image analysis, and the critical interparticle distance for PBT/PC was determined. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 54–62, 2006     

Influences of ethylene–butylacrylate–glycidyl methacrylate on morphology and mechanical properties of poly(butylene terephthalate)/polyolefin elastomer blends

Elastomer ethylene–butylacrylate–glycidyl methacrylate (PTW) containing epoxy groups were chosen as toughening modifier for poly(butylene terephthalate) (PBT)/polyolefin elastomer (POE) blend. The morphology, thermal, and mechanical properties of the PBT/POE/PTW blend were studied. The infrared spectra of the blends proved that small parts of epoxy groups of PTW reacted with carboxylic acid or hydroxyl groups in PBT during melt blending, resulting in a grafted structure which tended to increase the viscosity and interfere with the crystallization process of the blend. The morphology observed by scanning electron microscopy revealed the dispersed POE particles were well distributed and the interaction between POE and PBT increased in the PBT/POE/PTW blends. Mechanical properties showed the addition of PTW could lead to a remarkable increase about 10‐times in impact strength with a small reduction in tensile strength of PBT/POE blends. Differential scanning calorimetry results showed with increasing PTW, the crystallization temperature (T_c) and crystallinity (X_c) decreased while the melting point (T_m) slightly increased. Dynamic mechanical thermal analysis spectra indicated that the presence of PTW could improve the compatibility of PBT/POE blends. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40660.     

Nucleating agent induced impact fracture behavior change in PP/POE blend

This work was focused on the impact fracture behavior of polypropylene/ethylene-octene copolymer (PP/POE) blends with and without nucleating agent (NA). The crystallization morphologies of injection-molded-bar were analyzed by polarization optical microscope and the impact-fractured surface morphologies were characterized carefully through scanning electronic microscope. Our results show that the addition of 0.2 wt% α/or β-NA induces the great decrease of spherulites diameters companioned with the dramatically enhancement of PP/POE blend toughness. Virgin PP shows the typical brittle-fractured characteristic during the whole fracture process. PP/POE shows the less-ductile fracture feature with multiple-craze formation. The addition of NA into PP/POE blend changes the fractured surface feature from predominantly multiple-craze to predominantly shear yielding or shear yielding involving materials cavitations and second-crack re-initiation, respectively, indicating the change from brittle-like fracture mode to ductile fracture mode. The transformation of β → α during the impact process for β-NA nucleated samples has been observed; however, such transformation is suppressed by the presence of POE.     

新型热塑性弹性体增韧聚丙烯的研究

以聚烯烃弹性体(POE,乙烯-辛烯共聚物)为PP的增韧性剂,利用转矩流变仪、差示量热扫描(DSC)及力学性能测试方法,比较研究了PP/POE及PP/EPDM共混物的加工性能、结晶性能及力学性能;结果表明,POE在加工性、改性效果等方面比EPDM更具优势。还探讨了POE用量对PP/CaCO     

DCP用量对动态硫化POE/PP热塑性弹性体性能的影响

研究了过氧化二异丙苯(DCP)用量对动态硫化乙烯一辛烯共聚物聚丙烯(POE/PP)体系的物理性能以及PP结晶形态和POE相态结构的影响。结果表明:随DCP用量的增加,POE/PP体系的交联密度增大,而断裂伸长率、永久变形和拉伸强度下降。过量DCP的加人会导致PP降解,使体系的熔体流动速率随DCP用量的增加呈上升趋势。DSC分析表明,随着DCP用量的增加,POE/PP体系结晶度下降。微观分析得出,DCP对POE/PP体系相态结构影响显著,当DCP用量为1份时交联POE以较小的颗粒均匀分布于PP连续相中。     

Toughening effects of poly(butylene terephthalate) with blocked isocyanate‐functionalized poly(ethylene octene)

BACKGROUND: Blocked isocyanate‐functionalized polyolefins have great potential for use in semicrystalline polymer blends to obtain toughened polymers. In this study, poly(butylene terephthalate) (PBT) was blended with allyl N‐[2‐methyl‐4‐(2‐oxohexahydroazepine‐1‐carboxamido)phenyl] carbamate‐functionalized poly(ethylene octene) (POE‐g‐AMPC). RESULTS: New peaks at 2272 and 1720 cm^?1, corresponding to the stretching vibrations of NCO and the carbonyl of NH? CO? N, respectively, in AMPC, appeared in the infrared spectrum of POE‐g‐AMPC. Both rheological and X‐ray photoelectron spectroscopy results indicated a new copolymer was formed in the reactive blends. Compared to uncompatibilized PBT/POE blends, smaller dispersed particle sizes with narrower distribution were found in the compatibilized PBT/POE‐g‐AMPC blends. There was a marked increase in impact strength by about 10‐fold over that of PBT/POE blends with the same rubber content and almost 30‐fold higher than that of pure PBT when the POE‐g‐AMPC content was 25 wt%. CONCLUSION: The blocked isocyanate‐functionalized POE is an effective toughener for semicrystalline polymers. Super‐toughened PBT blends can be obtained when the POE‐g‐AMPC content is equal to or more than 15 wt%. Copyright © 2009 Society of Chemical Industry     

湿热老化对LDPE/POE结晶行为和力学性能的影响

在温度(40±2)℃,相对湿度93%条件下,研究了湿热老化对低密度聚乙烯(LDPE)与乙烯-辛烯共聚物(POE)共混物结晶行为和力学性能的影响。结果表明,随着湿热老化时间的延长,纯LDPE的拉伸强度以及POE用量分别为30%和70%共混物的断裂伸长率稍有增加。湿热老化对共混物的结晶行为产生了显著影响,且结晶行为的变化主要在老化前期完成。在老化中,POE的熔融峰和LDPE的低温熔融峰向高温方向漂移,并提高了共混物中LDPE在高温位置结晶的完善性和均一性。纯LDPE在老化过程中,小尺寸的晶体逐渐长大,结晶度逐渐增大,提高了LDPE结晶的完善性,且主要对LDPE(110)晶面产生明显的影响。