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1.
聚丙烯/三元乙现橡胶共混体系的研究   总被引:2,自引:0,他引:2  
研究了三元乙丙橡胶(EPDM)对聚丙烯(PP)结晶行为的影响以及PP/EPDM共混物的形态与性能的关系。EPDM对PP的熔点、结晶温度无明显影响,PP/EPDM共混物的结晶度随EPDM组份含量的增加而降低,适量的EPDM可使PP的晶体尺寸减小,晶胞参数与组份比无关。当EPDM用量为30% ̄40%时,共混物的冲击强度迅速提高。  相似文献   

2.
PP/PE共混物的拉伸力学性能   总被引:2,自引:0,他引:2  
应用Instron材料试验机,考察了室温下聚丙烯(PP)与低密度聚乙烯(LDPE)和高密度聚乙烯(HDPE)共混物的拉伸力学性能.结果表明,PP/LDPE共混物的拉伸强度和弹性模量与组份的关系符合对数混合法则。而PP/HDPE共混物的力学性能与组份的关系则较为复杂。  相似文献   

3.
热致性液晶共聚酯/聚丙烯共混物   总被引:4,自引:0,他引:4  
通过熔融共混制备了不同配比的(PHB/PET)/PP共混物,研究表明,共混物的弯曲弹性模量,弯曲强度及拉伸强度均比PP有所提高,当液晶含量为15%,PP-g-MAH为20%时,(PHB/PET)(PP-g-MAH)/PP三元共混物弯曲弹性模量最大,PP-g-MAH作为两相界面相容剂,改善了两相间的亲合性。DSC分析表明,共混物中PP相的结晶温度有较大幅度的提高,(PHB/PET)共聚酯起了PP结晶  相似文献   

4.
PP/HDPE/EPDM共混物的研究   总被引:2,自引:0,他引:2       下载免费PDF全文
研究了聚丙烯(PP)、高密度聚乙烯(HDPE)和EPDM共混制备非交联型PP/HDPE/EPDM三元共混物。结果表明,当共混比PP/HDPE/EPDM=65/20/15,活性碳酸钙为30份,HDPE品种为GF7750,采用先把HDPE和EPDM预制成混料再与PP共混的方法,可得到性能良好的PP/HDPE/EPDM共混物。  相似文献   

5.
PP/EPDM共混体系界面的研究   总被引:9,自引:2,他引:7  
本文采用马来酸酐对三元乙丙橡胶(EPDM)进行熔融接枝改性,将性后的EPDM与聚丙烯(PP)共混,对PP/EPDM和PP/EPDM-g-MAH两种共混体系的界面状况进行了对比。运用Huggins参数、界面张力参数对界面状况进行了表征;运用扫描电镜(SEM)和偏光显微镜对共混物的冲击断口形貌以及结晶情况进行了观察与分析;探讨了界面状况与共混物力学性能以及流变性能间的关系。  相似文献   

6.
EPDM粘度对PP\EPDM共混物断口形态和冲击性能的影响   总被引:2,自引:0,他引:2  
用机械共混的方法制备了一系列不同EPDM粘度的PP/EPDM共混物,对其力学性能和结晶行为进行了表征,并用扫描电子显微镜(SEM)研究了共混物冲击样条的断口形态。实验结果表明,EPDM粘度对共混物的冲击强度有较大影响,随着EPDM粘度的增大,共混物的冲击强度出现极大值,而结晶行为的变化则较小,研究共混物冲击样条的断口形态发现,共混物的冲击强度随EPDM粒径的变化出现极大值。  相似文献   

7.
EPDM/聚烯烃共混型热塑性弹性体的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
龚蓬  张祥福  张隐西 《橡胶工业》1996,43(8):451-457
制备EPDM/聚烯烃简单共混型热塑性弹性体。研究了聚合物种类、橡塑比、二元和三元共混对共混物力学性能的影响。结果表明,部分结晶性EPDM共混物的力学性能比无定形EPDM共混物好,部分结晶性EPDM与LDPE(低密度聚乙烯)共混物的拉伸强度大于两者的加和值,而其它二元共混物的拉伸强度均低于两共混单元的加和值;用LDPE部分替代PP,或用氯磺化聚乙烯(CSM)部分替代结晶性EPDM进行三元共混,能改善部分结晶性EPDM/PP共混物的某些性能。  相似文献   

8.
高流动性高韧性PP共混体系的研究   总被引:1,自引:1,他引:0  
吕英斌  杨军忠 《中国塑料》1999,13(11):28-33
本文采用三元乙丙胶(EPDM)和增韧母料对PP进行共混增废 性,同时采用降温母料的流动性,还探讨了LDPE、LLDPE、HDPE和马来酸酐接枝物等对体系性能的影响。运用扫描电(SEM)和偏光显微镜对共混物的微观结构和结晶状况进行了观察与分析,探讨了微观结构、结晶情况与共混物力学性能以及流动性间的关系。  相似文献   

9.
EPDM/PP热塑性弹性体的制备及性能研究   总被引:3,自引:0,他引:3  
以充油三元乙丙橡胶(EPDM),粉状聚丙烯(PP)、超细活性滑石粉为基本材料,采用动态硫化法在单螺杆挤出机组上制备EPDM/PP共混型热塑性弹性体(TPV);用力学性能试验及动态热流变仪方法测定了EPDM/PP-TPV的性能。结果表明,当EPDM充油量为20%-30%时,EPDM与PP熔融共混效果好;DCP用量为1.2%-1.5%时,EPDM/PP共混体系达到完全动态硫化;超细滑石粉最佳添加量为1  相似文献   

10.
PP/EVA-15共混物的研究   总被引:5,自引:0,他引:5  
应用SEM和力学性能测试研究了PP/EVA-15共混物原料配比、工艺条件和微观结构形态对材料性能的影响,对共混物的增韧机理进行了分析。与弹性体(EPDM)改性PP所作的比较显示,EVA-15对PP有良好的改性效果,其综合性能优于PP/EPDM共混物。  相似文献   

11.
高模量弹性体对PP结晶行为及力学性能的影响   总被引:2,自引:0,他引:2  
应用DSC和力学性能测试研究了PP/OTE、PP/EPDM共混物的结晶行为和它们的增韧作用。结果表明 ,烯烃类热塑性弹性体 (以下简称OTE)对PP的结晶性能无明显影响 ,EPDM对PP成核速率有促进作用。PP/OTE在赋予PP较好低温韧性的同时 ,使共混物的刚性得以适度兼顾 ,且易于加工。PP/OTE共混体系的综合性能优于PP/EPDM共混物  相似文献   

12.
The structure and properties of polyolefin blends of ethylene–propylene–diene terpolymer (EPDM) and polypropylene were studied. Blends were prepared in a laboratory internal mixer where EPDM was cured with PP under shear with dicumyl peroxide (DCP) at different shear conditions (blend–cure). Blends were also prepared for comparison from EPDM which were dynamically cured in the absence of PP and blended later (cure–blend). The effect of DCP concentration, intensity of the shear mixing, and rubber/plastic composition were studied. In blend–cure, the melt viscosity increased with increasing DCP concentration in blends of 75% EPDM and 25% PP, but it decreased with increasing DCP concentration in blends of 75% PP and 25% EPDM. In cure–blend, however, the melt viscosity increased with increasing DCP concentration for all compositions. The melt viscosity decreased with increasing intensity of the shear mixing presumably due to the formation of the smaller segregated microdomain of the crosslinked EPDM gels in both blend–cure and cure–blend materials. The crystallization rate was higher in EPDM/PP blends than in PP homopolymer. The crystallization rates for various blending conditions were also compared.  相似文献   

13.
以聚丙烯(T36F)为基料,考察了核-壳结构共聚物(SEP)和三元乙丙橡胶(EPDM)对聚丙烯的增韧作用。结果表明:SEP作为聚丙烯(PP)的增韧添加剂比EPDM有更好的增韧效果。当SEP用量为10phr时,PP/SEP共混材料的缺口冲击强度是纯PP的7.7倍,超过了20份EPDM增韧PP的效果,是优良的PP抗冲增韧改性剂。  相似文献   

14.
The control of miscibility for isotactic polypropylene (PP) and ethylene-propylene-diene terpolymer (EPDM) has been attempted by adding poly(ethylene-comethacrylic acid) (EMA) ionomers and by applying dynamic vulcanization. The rheological properties, crystallization behavior, and morphology of the dynamically vulcanized EPDM/PP/ionomer ternary blends were investigated with a Rheometrics dynamic spectrometer (RDS), a differential scanning calorimeter (DSC), and a scanning electron microscope (SEM). Two kinds of EMA ionomers neutralized with different metal ions (Na+ and ZN++) were investigated. Blends were prepared on a laboratory internal mixer at 190°C. Blending and curing were performed simultaneously, i.e., EPDM was vulcanized with dicumyl peroxide (DCP) in the presence of PP/ionomer. The composition of PP and EPDM was fixed at 50/50 by wt% and the contents of EMA ionomer were vaired from 5 to 20 parts based on the total amount of PP and EPDM. It was found that the addition of ionomers and the application of the dynamic vulcanization were effective in enhancing the miscibility of PP and EPDM. The structure of the blends was controlled by the following three component phases, i.e., the phase of the dynamially valcanized EPDM, PP, and Zn-neutralized ionomer. The ternary blends showed more miscibility than the PP/EPDM binary blend. This is due to the thermoplastic interpenetrating polymer network (IPN) of the ternary blends. The structure and properties of the ternary blends differed, depending on the types and contents of ionomer, i.e., the ternary blend containing Na-neutralized ionomer did not show a thermoplastic IPN structure clearly, even though the blend was prepared by dynamic vulcanization. The ternary blend containing Zn-neutralized ionomer clearly showed the behavior of a thermoplastic IPN when the contents of ionomer and DCP were 15 parts and 1.0 part, respectively.  相似文献   

15.
In this article, the morphology, crystallization, and rheological behaviors of polypropylene (PP)/ethylene‐propylene‐diene terpolymer (EPDM) binary blend and PP/EPDM/calcium carbonate nanoparticles (nano‐CaCO3) ternary blend were investigated. Two processing methods, i.e., direct extrusion and two‐step extrusion, were employed to prepare the PP/EPDM/CaCO3 blend. The influence of EPDM and nano‐CaCO3 respectively on phase morphology and properties of PP/EPDM blend and PP/EPDM/CaCO3 blend were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and dynamic rheometer. The crystallinity and crystallization temperature of PP/EPDM blend were improved in comparison to pure PP due to addition of EPDM, but kept invariable with the increased EPDM loading. As the EPDM content was increased, the mobility of PP molecular chains was weakened. Compared with direct extruded blend, less and finer nano‐CaCO3 was dispersed in matrix of two‐step extruded blend. Accordingly, the increased nano‐CaCO3 in matrix gave rise to a weaker increment in crystallinity and crystallization temperature of two‐step extruded blend, and a later platform of tanδ curve. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

16.
研究了三元乙丙橡胶/聚丙烯(EPDM/PP)共混物和动态硫化EPDM/PP热塑性弹性体(TPV)的等温结晶行为及形态结构,并用Avrami方程对其进行等温结晶动力学分析。结果表明,EPDM/PP共混物和EPDM/PP TPV的等温结晶行为符合Avrami方程,在相同的结晶温度下,TPV比共混物的Avrami指数小,半结晶时间短,结晶速率常数大;EPDM/PP共混物为双连续相结构,而EPDM/PP TPV是以硫化的细小橡胶颗粒为分散相、PP为连续相的"海-岛"结构,橡胶颗粒尺寸约为0.5μm。  相似文献   

17.
采用过氧化二异丙苯(DCP)降解聚丙烯(PP),熔融法制备了降解PP与三元乙丙橡胶(EPDM)共混物,采用差示扫描量热分析(DSC)及广角X射线衍射(WAXD)研究了降解PP/EPDM共混物的结晶行为,结果发现PP降解后β-PP晶型(300)消失 ;降解PP/EPDM共混物的非等温结晶过程是由成核控制的,并伴有明显的快速初级结晶和缓慢的次级结晶过程,降解PP以均相成核的三维球晶方式生长.  相似文献   

18.
Methylene diphenyl diisocyanate (MDI) affects the morphology, rheological, mechanical, and relaxation properties, as well as tendency to crystallize of PET in PET/PC/(PP/EPDM) ternary blends produced by the reactive extrusion. Irrespective of the blend phase structure, the introduction of MDI increases the melt viscosity (MFI dropped), resulting from an increase in the molecular weight of the polymer chains; the PET crystallinity was also reduced. MDI favors compatibility of PET with PC in PET/PC/(PP/EPDM) blends. This is explained by intensified interphase interactions on the level of segments of macromolecules as well as monomer units. The presence of MDI causes a substantial rise in the dynamic shear modulus within the high‐elastic region of PET (for temperature range between Tg,PET and that of PET cold crystallization); the processes of PET cold crystallization and melt crystallization become retarded; the glass‐transition temperatures for PET and PC become closer to each other. MDI affects insignificantly the blend morphology or the character of interactions between the disperse PP/EPDM blend and PET/PC as a matrix. PP/EPDM reduces the intensity of interphase interactions in a PET/PC/(PP/EPDM), but a rise in the degree of material heterogeneity. MDI does not change the mechanism of impact break‐down in the ternary blends mentioned above. Increased impact strength of MDI‐modified materials can be explained by higher cohesive strength and resistance to shear flow at impact loading. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

19.
The melt grafting of vinyltrimethoxysilane (VTMS) onto polypropylene (PP)/ethylene-propylene diene terpolymer (EPDM) blends was studied. The effect of VTMS, EPDM and initiator concentrations on mechanical properties, melt flow index (MFI) and gel content of the modified PP/EPDM samples were investigated. The influence of coagents, i.e. styrene and trimethylolpropane trimethacrylate was also studied. Scanning electron microscopy (SEM) was used to observe the fractured surface of PP/EPDM and the modified PP/EPDM blends. The VTMS grafting reaction was in situ monitored using differential scanning calorimetry (DSC). Moreover, the thermal and crystallization behavior of VTMS-crosslinked PP/EPDM blends were studied by thermogravimetric analysis (TG) and DSC, respectively. It had been found that the thermal stability of VTMS-crosslinked PP/EPDM was improved. DSC measurements showed that the grafting reaction occurs from 170 to 220 °C and the crystallization temperatures increased compared with those of the untreated PP/EPDM.  相似文献   

20.
硫酸钙晶须/PP/EPDM复合材料的流变行为   总被引:4,自引:0,他引:4  
利用Instron 3211型毛细管流变仪研究了硫酸钙晶须/PP/EPDM复合材料的流变行为,讨论了剪切速率、温度、晶须含量对PP/EPDM共混物表观粘度的影响。结果表明,该共混体系属于假塑性流体,硫酸钙晶须在低添加量时对PP有降粘作用;加入30%硫酸钙晶须的PP/EPDM体系,粘流活化能略高于未加晶须的体系,两个体系均为温敏性材料。  相似文献   

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