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1.
PP/EPDM/CaCO2三元共混体系的脆韧转变研究   总被引:12,自引:0,他引:12  
采用扫描电镜和材料力学性能试验方法研究了PP/EPDM/CaCO3三元体系中CaCO3的表面处理与其材料的缺口冲击韧性及产生脆韧转变现象之间的关系。实验结果及分析表明,体系中分散相颗粒周围向PP基体扩散,渗透或与之共结晶的EPDM部分是增韧PP的有效成分;  相似文献   

2.
HDPE,LLDPE及EPDM对PP非等温结晶行为的影响   总被引:2,自引:0,他引:2  
采用等速率温DSC法研究了HDPE、LLDPE及EPDM对PP非等温结晶行为的影响。结果表明,PE的加入使用PP的结晶峰温度升高,熔点下降,且使结晶速率加快,球晶细化。HDPE先先PP结晶,燕促使PP/HDPE共混物中的PP异相成核。  相似文献   

3.
PP/EPDM/CaCO_3三元共混体系的脆韧转变研究   总被引:12,自引:0,他引:12  
采用扫描电镜和材料力学性能试验方法研究了PP/EPDM/CaCO3三元体系中CaCO3的表面处理与其材料的缺口冲击韧性及产生脆韧转变现象之间的关系。实验结果及分析表明:体系中分散相颗粒周围向PP基体扩散、渗透或与之共结晶的EPDM部分是增韧PP的有效成分;较好的表面处理条件下,体系中加入较少量的EPDM即可使材料缺口冲击韧性和拉伸模量值同时达到较好水平。  相似文献   

4.
PP三元共混合金的力学性能及结晶行为研究   总被引:5,自引:0,他引:5  
研究了不同乙烯含量的EPDM对PP/UHMWPE合金的增容作用,并讨论了共混体系结晶行为的变化情况。发现EPDM中乙烯含量的增加可提高增容效果;在PP/UHMWPE/EPDM为100/10/6时,共混物缺口冲击强度可达91.1kJ/m^2,为PP的3.5倍,此时拉伸强度仍比纯PP高4.3MPa。  相似文献   

5.
几类重要的反应性高分子应用研究进展   总被引:1,自引:0,他引:1  
本文主要叙述了PE-g-MAH,PP-g-MAH,EPDM-g-MAH,PS-g-GMA,SEBS-g-GMA,PP-g-AA等几种反应性高分子的制备及应用,研究现状和它们未来发展的趋势。  相似文献   

6.
PET/HDPE共混物的形态结构及力学性能的研究   总被引:9,自引:0,他引:9  
利用IR、SEM、DSC和力学测试等分析方法,研究了熔融接枝高密度聚乙烯(HDPE-g-MA)和界面改性剂(IM)对PET/HDPE共混物形态结构、界面偶联状况和力学性能的影响。结果在明,HDPE-g-MA改善了PET与HDPE的相容性,使HDPE较均匀地分散在PET基体中,但并未检测到PET/HDPE-g-MA界面有化学反应发生。界面改性剂的作用在于,一方面通过提高PET基体的粘度,并接近HDPE相的粘度而使分散相细化;另一方面通过与HDPE-g-MA和PET的偶联反应而增强了PET/HDPE-g-MA界面粘结,从而显著地提高了共混物的抗冲击性能。  相似文献   

7.
聚苯醚与含有机硅嵌段共聚物共混的研究   总被引:1,自引:0,他引:1  
利用差热扫描量热计(DSC)、动态粘弹谱仪(DDV)和力学性能测试等手段研究了PPO/PHS-PDMS、PPO/PPO-PHS-PDMS和PPO/PS/PPO-PHS-PDMS3个共混体系的形态结构和性能。结果表明,PPO/PHS-PDMS为一相容体系。当PPO分子量与PPO-PHS-PDMS中PPO分子量相同时,PPO/PPO-PHS-PDMS与PPO/PS/PPO-PHS-PDMS是两个相容体  相似文献   

8.
HDPE、LLDPE及EPDM对PP等温结晶行为的影响EI   总被引:3,自引:0,他引:3  
采用DSC法研究了HDPE、LLDPE及EPDM对PP等温结晶行为的影响。结果表明,PE的存在可显著降低PP的结晶速度,且HDPE比LLDPE的影响要大,但加入EPDM后有所改善;PE的存在会诱发PP生成亚稳态的β晶系,β晶的生成量只与PE的含量有关,而与种类无关。  相似文献   

9.
EPDM磺酸镁盐对HDPE填充体系力学性能影响的研究   总被引:2,自引:0,他引:2  
合成了三元乙丙橡胶磺酸镁盐(Mg-SEPDM)离聚体,测定了该离聚体的磺化度,研究了HDPE/Mg-SEPDM/金属氢氧化物三元体系的力学性能,通过SEM和多功能内耗仪对该体系的形态结构和动态力学性能进行了探讨。结果表明,Mg-SEPDM中的离子基团通过物理交联可以增加HDPE的韧性,增强HDPE与金属氢氧化物的界面强度,提高体系的综合力学性能。  相似文献   

10.
聚醚砜微孔膜制备中非溶剂添加剂作用研究   总被引:25,自引:8,他引:17  
以聚醚砜(PES)为膜材料,DMAc为溶剂,研究了3种非溶剂加剂(NSA)-EgOH,DeOH和BuOH在水和NSA中凝胶对于板微孔膜性能的影响,利用浊点法得到PES/DMAc/NSA和PES/DMCs/NSA/H2O体系25℃的相图,并以邻近比α值来表征膜溶液组成点靠近相分离的程度,添加了NSA的铸膜液在水中凝胶制备微孔膜,以EgOH为非溶剂添加物,在相同聚合物浓度,相同凝胶条件下,仅仅改变铸膜  相似文献   

11.
High density polyethylene (HDPE) was added to the polypropylene (PP)/ethylene-propylene diene terpolymer (EPDM) binary blend, and the effect of testing temperatures on the modulus of elasticity, impact behavior and corresponding fracture morphology was analyzed. Modulus of elasticity generally decreased as the EPDM content increased regardless of the testing temperatures. However, it was found that the modulus of elasticity of PP/EPDM/HDPE ternary blend increased compared to PP/EPDM binary blend when tested at –30 and –60 °C. Notched Izod impact strength changed depending on the testing temperatures, however, there was not much difference between binary and ternary blends up to 20 wt% EPDM. However, at more than 30 wt% EPDM content, ternary blends showed higher impact strength compared to binary blends. Especially, at –30 °C, brittle-ductile transition was observed between 20 and 30 wt% EPDM. Subsurface morphology was also analyzed, and the relationship between the impact strength and the stress whitening zone was investigated. Scanning electron microscopy observation of impact fractured surfaces was conducted, and overall morphology was analyzed with respect to HDPE addition and testing temperature change.  相似文献   

12.
用FT-IR方法研究了PP/EPDM共混物表面与本体的结晶形态,结果表明,随着EPDM含的增加,997cm^-1吸收峰的位置不变,但峰宽变小,测算PP的结晶度的A998/A972比值随着变化,从表面与本体比较来看,一是表面PP结晶状态吸收峰是在997.0cm^-1,而本体系在997.8cm^-1即向低波数方向移动;二是表面非结晶状态吸收峰972cm^-1增加较多,这都都共混物表面与本体PP结晶度及  相似文献   

13.
Craig Clemons 《Composites Part A》2010,41(11):1559-1569
Blends of polyethylene (PE) and polypropylene (PP) could potentially be used as matrices for wood–plastic composites (WPCs). The mechanical performance and morphology of both the unfilled blends and wood-filled composites with various elastomers and coupling agents were investigated. Blending of the plastics resulted in either small domains of the minor phase in a matrix of major phase or a co-continuous morphology if equal amounts of HDPE and PP were added. The tensile moduli and yield properties of the blends were clearly proportional to the relative amounts of HDPE and PP in the blends. However, the nominal strain at break and the notched Izod impact energies of HDPE were greatly reduced by adding as little as 25% of the PP. Adding an ethylene–propylene–diene (EPDM) elastomer to the blends, reduced moduli and strength but increased elongational properties and impact energies, especially in HDPE-rich blends. Adding wood flour to the blends stiffened but embrittled them, especially the tougher, HDPE-rich blends, though the reductions in performance could be offset somewhat by adding elastomers and coupling agents or a combination of both.  相似文献   

14.
Polypropylene (PP)/ethylene–propylene-diene monomer (EPDM)/zinc dimethacrylate (ZDMA) blends with remarkable toughness and extensibility were successfully prepared via peroxide dynamical vulcanization. A unique structure with the EPDM particles surrounded by a transition zone containing numerous polymerized ZDMA (PZDMA) nano-particles was observed for the first time by using transmission electron microscopy (TEM) examination, which contributed to the dramatically increase of Izod impact strength. Dynamic mechanical analysis (DMA) confirmed that the possible PZDMA graft products resulted from peroxide dynamical vulcanization improved the compatibility between EPDM and PP phases. The specific morphology of the PP/EPDM/ZDMA blends indicated that ZDMA can lead to size reduction and good distribution uniformity of the crosslinked rubber particles and the increase of adhesion between PP matrix and EPDM phases during deformation. The synergic effect of the increase in the effective volume of the EPDM phase, the improved compatibility and adhesion between EPDM and PP phases and the deformation of those fine rubber particles is believed to result in the remarkable high toughness and extensibility of the PP/EPDM/ZDMA blends. Particularly for the PP/EPDM ratio of 70/30, the PP/EPDM/ZDMA (70/30/9, w/w/w) ternary blends with the Izod impact strength nearly 2 times higher than PP/EPDM (70/30, w/w) binary blends and 15–20 times higher than PP are achieved; besides, the elongation at break of PP/EPDM/ZDMA ternary blends is 4–5 times higher than that of PP/EPDM binary blends.  相似文献   

15.
借助扫描电子显微镜观察了PP/EPDM共混物注射成型样条的冲击断口形态以及该共混物注射产条的芯-壳结构特征,研究了EPDM基体中的各向异性分布,不同冲击强度样品的断口形态以胶芯-壳结构和EPDM的各向异性分布对断口形态和冲击性能的影响。  相似文献   

16.
在三螺杆动态混炼挤出机上,研究了不同橡塑比的(三元乙丙橡胶)EPDM/(聚丙烯)PP共混物经动态混炼和稳态混炼挤出后的拉伸性能.振动频率和振幅对共混物的拉伸强度均有很好的强化作用,并分析了振动力场对EPDM/PP共混物影响的规律和振动强化效果.  相似文献   

17.
动态硫化EPDM/PP热塑性弹性体动态力学性能的研究   总被引:14,自引:1,他引:13  
应用动态热力学分析仪测定了动态硫化EPDM/PP共混物的动态力不宪为,Tg峰的变化,表明P的非晶部分与EPDM具有部分互溶性,同时讨论了共混物动态模量的特点,研究了不同橡塑比,硫化剂和软化剂用量对动态硫化EPDM/PP共混物动态力学性能的影响。  相似文献   

18.
本文通过TEM和毛细管流变仪对EPDM磺酸盐及其与HDPE共混物形态结构和流变行为进行了研究。实验结果表明,随磺化度的增大,离子聚集更为明显,EPDM磺酸盐的熔体表观粘度显著增加,导致共混物熔体表观粘度增加。经硬脂酸锌(ZnSt)增塑后,EPDM磺酸锌盐(Zn-SEPDM)熔体表观粘度将下降,通过加入ZnSt可望改善HDPE/Zn-SEPDM的加工性能。  相似文献   

19.
Blends of isotactic polypropylene and ethylene propylene diene (EPDM) rubber were dynamically vulcanized using the dimethylol phenolic resin/stannous chloride crosslinking system. The EPDM blends are thermally more stable than polypropylene (PP). Dynamic curing rendered the vulcanizate thermally more stable than unvulcanized blends. The variations in degree of crosslinking and degree of crystallinity are the main factors for observed increase in thermal stability of vulcanized blends. Degree of crosslinking increases the interfacial adhesion between the PP and EPDM phases. Dimethylol phenolic resin used as a compatibilizer also enhanced the thermal stability of the PP/EPDM blends. Crystallization of PP in the blends of PP/EPDM was also studied through modulated differential scanning calorimetry. Other detailed analyses of endotherm peaks obtained after first and second melts in terms of heat of enthalpy, degree of undercooling, and degree of crystallinity were also evaluated. Kinetic parameters were also determined.  相似文献   

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