一步法反应性共混制备PA66／HDPE合金

在双螺杆挤出机上通过一步法反应性共混制备了聚酰胺66（PA66）/高密度聚乙烯（HDPE）合金。使用扫描电镜，Molau实验等方法研究了共混物的形态，并且比较了由一步法反应性共混得到的合金材料与PA66/HDPE简单共混物，以及二步法共混合金在干，湿态下的力学性能。结果表明：采用将PA66、HDPE、马来酸酐，以及引发剂加入双螺杆挤出机进行一步法反应共混的方法可以得到与二步法共混合金形态和性能相似的塑料合金，PA66的韧性可以得到明显改善。     

VC／BA共混物增容PVC／HDPE共混体系的研究

采用氯乙烯—丙烯酸丁酯(VC/BA)共混物作为聚氯乙烯(PVC)/高密度聚乙烯(HDPE)共混物的增容剂,通过冲击实验、拉仲实验、动态力学分析,系统地研究了共混体系性能与其结构之间的关系。通过Brabender流变仪测定了VC/BA共混物增容PVC/HDPE共混体系的流变性能。结果表明,VC/BA共混物是PVC/HDPE共混体系的良好增容剂。在一定范围内,VC/BA共混物与HDPE对PVC有协同增韧效应。vC/BA和HDPE的加入改善了PVC的塑化和流变性能     

废胶粉／HDPE热塑性弹性体的制备研究

考察了废胶粉粒径和用量、共混时间、温度以及EVA用量对废胶粉/高密度聚乙烯(WRP/HDPE)力学性能的影响.获得了制备性能良好的WRP/HDPE共混物的条件为:WRP/HDPE的质量比为50/25、共混时间为22 min、共混温度为170 ℃以及EVA用量为总质量的23%.共混材料的微观结构研究结果表明,EVA的加入增强了共混物之间的界面结合力,提高了共混物的物理机械性能.力学性能的研究表明,该共混材料可作为热塑弹性体使用.     

PP／HDPE／弹性体三元共混体系的力学性能,形态及应用

本文叙述PP/HDPE/弹性体三元共混体系的力学性能、形态特征与组成配比的关系。研究结果表明,PP/HDPE/弹性体三元共混可以制成具有高冲击性能的PP改性材料,常温缺口冲击强度大于40kJ/m~2,其他力学性能较均衡,加工性能良好。HDPE的品种和用量以及弹性体的品种和用量对PP三元共混物的力学性能及形态有较大的影响。实验结果表明,当弹性体用量在20%范围内,组成的PP/HDPE复合基体才能获得高冲击性能的三元共混物。在PP/HDPE共混物内,HDPE对PP球晶起到插入和分割作用,使PP球晶变得不完整,被分割成晶片。当HDPE含量较高时,PP只能生成尺寸较小的结晶碎片(细化),与此形态对应,可获得高冲击强度的PP/HDPE共混物。当弹性体(Ⅰ)掺混于PP/HDPE时,弹性体起着类似于HDPE对PP晶体的插入、分割和细化作用,而且弹性体的这种作用更强于HDPE。文中还简叙了PP三元共混物的应用情况。     

原位增容等规聚丙烯/高密度聚乙烯共混物的制备及性能研究

以自由基支化反应为基础,在等规聚丙烯/高密度聚乙烯(iPP/HDPE)共混物中加入过氧化物、自由基调节剂和多官能度丙烯酸酯类单体进行共支化反应,以经济便捷的方式原位生成了长链支化共聚物,对iPP/HDPE共混物进行高效增容。结果表明:加入少量的添加剂就能大幅度提升iPP/HDPE共混物的力学性能,如原位增容使iPP/HDPE(50/50)共混物的断裂伸长率和缺口冲击强度提升约3倍。此外,与纯iPP/HDPE共混物相比,改性样品的耐环境应力开裂时间大幅提高,iPP与HDPE的Tg靠近,且球晶尺寸变小,表明原位增容极大地改善了iPP/HDPE共混物中iPP与HDPE的相容性。     

PA6／HDPE／EVA三元共混改性的研究

研究了PA6/HDPE、PA6/HDPE/EVA共混物的密度、热性能和力学性能。PA6/HDPE/EVA三元共混物的力学性能比PA6/HDPE二元共混物有明显提高。对于拉伸强度,EVA的最佳含量在2～4份。冲击强度随EVA含量的增加而提高,EVA的含量小于5份时,对共混物的硬度几乎没有影响。     

电子辐照HDPE对HDPE／PET的增容作用

通过用电子束辐照高密度聚乙烯(HDPE),引入极性基团到HDPE中,增加了HDPE与聚对苯二甲酸乙二醇酯(PET)共混体系的相容性。辐照的HDPE与PET共混,使共混转矩和比能量消耗增加;但HDPE辐照一个月后再与PET共混,则使共混转矩和比能量消耗降低。力学性能数据表明,辐照的HDPE对HDPE/PET共混体系具有增容作用。     

十八烷基缩水甘油醚的合成及其增容尼龙6/高密度聚乙烯共混体系的研究

利用十八醇和环氧氯丙烷反应合成了十八烷基缩水甘油醚(OGE),并将其作为熔融共混方法中的增容剂,制备了尼龙6(PA6)/高密度聚乙烯(HDPE)共混材料。研究了OGE用量对共混物的热性能、结晶行为、形态结构、力学性能及吸水性的影响。结果表明,OGE促进了HDPE在PA6基体中的分散,在保持共混材料吸水率的同时,有效改善了共混物的力学性能,与未加入增容剂的PA6/HDPE共混物相比,OGE含量为2.9%(m/m)时,共混材料的缺口冲击强度、拉伸模量、断裂伸长率、弯曲强度分别提高了12%、33%、95%、6%,拉伸强度基本保持不变,而弯曲模量下降了8%。     

PP／HDPE／SBS三元共混物的研究——形态结构与性能

研究了PP/HDPE/SBS三元共混物的性能及形态结构特征。研究结果表明,PP三元共混物的冲击韧性除与SBS的含量密切相关外,还与HDPE的含量有关,HDPE起到了与SBS相似的增韧作用。由于HDPE的掺入,减少了SBS的含量,制成了一种力学性能均衡的超高韧性PP三元共混材料。形态结构的研究表明,共混物中,SBS呈颗粒状分布,另外SBS还与HDPE组成了具有包藏结构的复合粒子。     

长链烷基封端PLA的合成及其增容PLA/HDPE共混体系的研究

用十八烷基缩水甘油醚(OGE)对聚乳酸(PLA)的端羧基进行封端反应制备了十八烷基封端聚乳酸(OCP),并将其作为增容剂,采用熔融共混的方法制备了PLA/高密度聚乙烯(HDPE)共混材料。研究了OCP用量对共混物的热性能、结晶行为、形态结构、耐热性及力学性能的影响。结果表明,OCP有利于提高共混物的结晶速率、可促进HDPE在PLA中的分散;当OCP质量分数为2.7%时,共混材料的维卡软化温度提高了13%,冲击强度提高了19%。     

Effect of maleic anhydride grafting on nanokaolinclay reinforced polystyrene/high density polyethylene blends

Nanofillers have revolutionized the field of polymer modification. Modification of polymer blends with nanofillers opens up a myriad of opportunities to develop materials of choice. Polystyrene (PS) and high density polyethylene (HDPE) are two widely used standard plastics. To generate high modulus and strength a PS rich blend of PS/HDPE (80/20) was selected and the blend was modified using low cost nanokaolin clay, a 1:1 alumina silicate. The effect of maleic anhydride grafted PS/PE as compatibilizer in this system was studied. The incorporation of the compatibilizer improves the mechanical properties. This can be correlated with better interfacial adhesion as evidenced by scanning electron microscopy. The optimum in these properties was obtained at a compatibilizer concentration of 10–15%. The composites were characterized byX‐ray diffraction, differential scanning calorimetric, and dynamic mechanical analyzer techniques. This study shows that kaolin can be used as potential modifier of PS/HDPE blend. POLYM. COMPOS. 2012. © 2012 Society of Plastics Engineers     

Improvement of the mechanical properties of an HDPE/PS blend by compatibilization and incorporation of CaCO3

Generally, recycled polymer blends exhibit solid dispersion‐like morphology with poor mechanical properties. The aim of this work was to enhance the mechanical properties of a HDPE/PS (75/25) blend, in particular the stiffness and the impact strength. In order to improve the stiffness, CaCO₃ filler was incorporated. It was shown that PS and CaCO₃ were separately dispersed with poor adhesion to the HDPE matrix. The incorporation of CaCO₃ significantly enhanced the stiffness but lowers the impact resistance. Elastomer copolymers were incorporated in order to compensate for the embrittlement caused by the CaCO₃ filler. Depending on their chemical structure, either grafted with a reactive function or ungrafted, the elastomers acted differently at the interfaces of the HDPE/PS/CaCO₃ system. SEBS acts exclusively at the HDPE‐PS interface whereas SEBSgMA acts at both the HDPE‐PS and the HDPE‐CaCO₃ interface. The SEBSgMA elastomer lowered the stiffening effect caused by CaCO₃ and provided an insufficient increase in impact properties. One the other hand, SEBS, which concentrates its action at the HDPE‐PS interface, retained much of the stiffening effect of CaCO₃ and provided a greater improvement in impact properties than SEBSgMA. In the recycled HDPE/PS (75/25) blend, the incorporation of 20 vol% CaCO₃ and 4 vol% SEBS led to an increase in both impact strength (from 39 to 70 kJ/m²) and in stiffness (from 1335 to 1560 MPa). So, encouraging results were obtained, enabling us to predict a promising future for this approach to the recycling of commingled plastics.     

SEBS/HDPE共混物加工性能及力学性能的研究

以苯乙烯-乙烯-丁二烯-苯乙烯嵌段共聚物（SEBS）／高密度聚乙烯（HDPE）为共混改性的研究对象，采用哈克转矩流变仪进行共混，讨论了不同用量、不同类型的HDPE对共混物加工流变性能、冲击性能和拉伸性能的影响。结果表明，当添加的HDPE份数达到20phr时，能显著提高共混物的冲击性能和拉伸性能，同时共混物的加工流变性能也有了很大的改善。因此质量比为100／20的SEBS／HDPE体系是一个比较理想的共混体系。     

In situ compatibilization of a polyethylene,polypropylene, and polystyrene ternary blend through Friedel–Crafts alkylation

The Friedel–Crafts alkylation reaction has been applied to reactively compatibilize a ternary blend of high-density polyethylene (HDPE), polypropylene (PP), and polystyrene (PS). The reactions were carried out in an internal mixer using varying catalyst concentrations. The resulting compatibilizer was quantified after Soxhlet extraction. In addition, p-substitution due to the grafting of alkyl groups onto the PS benzene ring was identified via nuclear magnetic resonance spectroscopy. The size of the PS domain in the reactive compositions is decreased by 80%. Moreover, the phase in which PS droplets were dispersed varied, that is, in the nonreactive blends they were found in the PP phase and in the reactive blends they shifted toward the HDPE phase. The effect of the compatibilizing agent was to improve the mechanical properties of the blend. Even with the lowest catalyst content, the properties of elongation-at-break, tensile strength, toughness, and elastic modulus showed improvements. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48295.     

马来酸二丁酯接枝PE的性能及应用

研究了由反应性挤出接枝技术制得的聚乙烯接枝马来酸二丁酯(PE-DBM)产品的性能及使用情况。实验发现,PE-DBM具有与PE相同的成型加工性,PE-DBM中部分游离态单体对后加工使用无不良影响.其应力-应变性能优于相应的PE。流变学研究表明PE-DBM是符合幂律方程的非牛顿型假塑性流体。PE-DBM适合与极性表面的填料共混并作为相容剂具有良好的效果。     

HDPE/POE/CaCO3三元体系薄膜研究

采用聚烯烃弹性体（POE）和重质碳酸钙对HDPE薄膜进行改性,研究了POE和重质碳酸钙的用量对共混体系薄膜力学性能、流变性能的影响。结果表明,POE的加入,使HDPE／POE薄膜的单位落镖冲击破损质量增加,而拉伸强度则有所下降。当POE的质量分数为10％时,薄膜的单位落镖冲击破损质量提高了51．1％,但薄膜的拉伸强度下降了20．5％。在HDPE／POE／CaC03体系中,当POE、重质碳酸钙的质量分数分别为10％和5％时,薄膜的单位落镖冲击强度比纯HDPE提高95．6％,且拉伸强度不降低。     

Weld lines and mechanical properties of injection molded polyethylene/polystyrene/copolymer blends

In this article, we investigate the effect of weld lines on the tensile mechanical properties of unmodified and copolymer modified high density polyethylene (HDPE) and polystyrene (PS) blends. The homopolymers were melt blended in the proportion of 20 wt% HDPE and 80 wt% PS using a twin screw extruder at a temperature of 200°C. The results show that the mechanical properties are generally lower when weld lines are present. The decrease of the mechanical properties is much more pronounced for the blends. The addition of small amounts of a commercial styrene/butadiene copolymer significantly improves the strength and the elongation at break of this blend. An optimum copolymer concentration was observed at 3 wt%. This value coincides with the interphase saturation concentration of the copolymer obtained from the analysis of the DMTA (dynamic mechanical and thermal) properties of the blends. The copolymer was also found to induce important changes in the morphology of the blend. The interdiffusion of the polymer fronts in the weld region was also improved by the presence of the copolymer. It is believed that these two aspects contribute to the enhanced properties obtained with copolymer modified blends in presence of weld lines. An important effect of the injection temperature on the tensile strength and the elongation at break of welded samples with copolymer modified blends was observed. The effect of mold temperature on these properties was less important mainly at low injection temperatures. Only a slight effect of these two parameters was observed for the tensile modulus in the range of mold and injection temperatures considered in this study.     

聚碳酸酯—聚苯乙烯的反应性挤出共混研究(Ⅰ)

研究了噁唑啉官能化聚苯乙烯(RPS)与聚碳酸酯(PC)的共混反应,对反应性共混物及相应的非反应性共混物作了应力-应变试验及动态力学分析(DMA),并测定其接枝率及密度,发现反应性挤出共混提高了PS/PC共混物的力学性能。     

HDPE/硫化胶粉共混材料的研究

研究了HDPE／硫化胶粉共混材料的力学性能和流动性能。结果表明,硫化胶粉与HDPE有良好的混合性能,共混材料的冲击性能化胶粉含量增加而提高,但共混材料的拉伸强度和流动性能有所下降。添加5％的PE－g－MAH进行增容,可使共混材料的力学性能明显提高。