硅灰石与连续玻璃纤维毡组合增强聚丙烯的力学性能

采用硅灰石与连续玻璃纤维毡组合增强聚丙烯,研究了硅灰石的含量,玻璃纤维毡的面密度、基体树脂的性质及界面改性等对材料力学性能的影响。结果表明：采用硅灰石与连续玻璃纤维毡组合增强,可提高复合材料的拉伸、弯曲强度及模量,但过高的硅灰石含量,会导致拉伸及弯曲强度下降,材料的力学性能随着所用玻璃纤维毡面密度的增大而显著提高,采用偶联剂对硅灰石进行处理及在基体聚丙烯中添加功能化聚丙烯,可改善界面结合、提高材料性能,随着功能化聚丙烯含量的增加,材料的拉伸、弯曲强度及模量有所提高,但含量过高时,会引起材料冲击强度的下降;组合增强材料的性能与基体树脂本身的力学性能密切相关,同时还受基体树脂熔体流动性的影响。     

再生家电壳体聚丙烯材料性能改善研究

再生家电壳体聚丙烯材料通过玻璃纤维增强改性可以显著提升材料的拉伸强度及弯曲模量,但由于再生聚丙烯材料中杂质的影响,材料的缺口冲击强度没有获得明显提升。从改善再生家电壳体聚丙烯材料性能的角度出发,通过掺入再生聚丙烯、添加弹性体和改变玻璃纤维直径等研究了改性材料的性能差异。在全新聚丙烯与再生聚丙烯共混体系中,随着再生聚丙烯含量增加,改性材料的弯曲模量无明显变化,但缺口冲击强度急剧下降。当再生聚丙烯添加质量分数大于30%时,改性材料的缺口冲击强度下降35%。在玻璃纤维增强再生聚丙烯体系中,通过添加质量分数为5%的弹性体,可以显著改善改性材料的缺口冲击强度,同时保持良好的拉伸强度与弯曲模量;使用小直径玻璃纤维可以明显改善改性材料的缺口冲击强度,当玻璃纤维直径由14μm降低至10μm时,缺口冲击强度由8 kJ/m²提升至11 kJ/m²。     

镁盐晶须/聚丙烯复合材料的研究

研究了镁盐晶须／聚丙烯复合材料的力学性能和耐热性能。结果表明：随着镁盐晶须用量的增加，复合材料的拉伸强度、弯曲强度、弯曲模量及热变形温度显著提高，而简支梁缺口冲击强度基本保持不变。利用马来酸酐接枝聚丙烯作为相容剂，可以改善基体树脂与镁盐晶须的界面结合性，有助于提高力学性能。     

高刚耐热聚丙烯树脂的制备

以牌号140聚丙烯树脂作为基料,使用高效成核剂生产出一种高刚耐热聚丙烯树脂。文中分析了制备高刚耐热聚丙烯树脂时,成核剂的种类和添加比例对改性PP(140)性能的影响。筛选出添加0.10wt%CHJ-3#成核剂制备的高刚耐热聚丙烯树脂力学性能最佳,其拉伸强度达到40.8 MPa,拉伸断裂标称应变为10.63%,拉伸断裂应力35.1 MPa,弯曲模量为1994.63MPa,邵氏硬度为71.9,悬臂梁冲击强度为3.33 k J/m~2,负荷热变形温度高达122℃。     

DCP对长玻纤增强聚丙烯复合材料性能的影响

长玻纤增强聚丙烯复合材料采用熔体浸渍工艺制备,研究过氧化二异丙苯(DCP)对长玻纤增强聚丙烯复合材料性能的影响。结果表明:随着DCP用量的增加,长玻纤增强聚丙烯复合材料的拉伸强度、弯曲强度、缺口冲击强度、弯曲模量均先增加后降低,通过动态力学性能和形态分析得出,当DCP添加量为0.4%时,长玻纤增强聚丙烯复合材料的拉伸强度、弯曲强度、弯曲模量和缺口冲击强度均最高。     

基体树脂与短玻纤对聚丙烯复合材料性能影响研究

选取不同熔体流动速率（MFR）的均聚聚丙烯（i-PP）、共聚聚丙烯（co-PP）作为基体树脂,研究短玻纤（GF）对不同类型聚丙烯复合材料力学性能以及MFR的影响。结果表明：聚丙烯基体种类对复合材料的MFR以及冲击强度起关键作用。随着GF含量的增加,聚丙烯复合材料的拉伸强度、弯曲模量逐渐增加,收缩率逐渐降低,冲击强度变化幅度较小。随着取向角度逐渐增加,聚丙烯复合材料的拉伸强度迅速下降。当取向角度为90°,材料的拉伸强度低于取向角度为0时的1/2。     

添加剂对PVC/ABS合金力学性能的影响

向PVC/ABS合金体系中分别加入AS树脂、MBS树脂、EP和DOP,实验结果发现,加入适量的AS、EP,体系韧性明显下降,弯曲强度、弯曲模量有所提高,MBS的加入提高了PVC/ABS合金的冲击强度,但是弯曲强度和弯曲模量下降明显,DOP的加入使得PVC/ABS合金体系的冲击强度、弯曲强度及弯曲模量都有明显下降,降低了体系的力学性能。     

聚丙烯瓶盖树脂的中试开发和工业化生产

在聚丙烯中试装置上进行催化剂和助剂配方的筛选以及聚合工艺的优化等研究,开发了聚丙烯瓶盖专用树脂YPJ-706,并在工业装置上生产出弯曲模量大于1.4 GPa,常温冲击强度大于或等于8.0 kJ/m2的高性能产品,可满足瓶盖制品的加工要求.     

PP／EPDM复合材料性能研究

研究了聚丙烯（PP）／三元乙丙橡胶（EPDM）复合材料的结构、制备条件对复合材料力学性能的影响。结果表明：该复合材料拉伸强度、弯曲强度争弯曲模量主要是由连续相PP决定;EPDM在PP中的分布和形态影响材料的冲击性能;随着EPDM含量的增加材料的冲击强度提高到46．9kJ／m^2,断裂伸长率最大可达770％,但复合材料的流动性能略有下降。     

磷酸酯盐成核剂对聚丙烯性能的影响

以均聚聚丙烯(PP)为基体树脂,通过添加磷酸酯盐类成核剂TMP-1等改性方式,研究了该成核剂在不同添加量下对PP弯曲模量、拉伸屈服强度、悬臂梁缺口冲击强度以及热变形温度等性能的影响,通过差示扫描量热仪(DSC)与带可程序升降温控制热台的偏光显微镜(POM)考察了成核剂对PP结晶性能的影响。力学性能测试及偏光显微镜微观观察表明,磷酸酯盐类成核剂TMP-1可以有效提高PP的弯曲模量、拉伸屈服强度、热变形温度以及结晶速度,但是,悬臂梁缺口冲击强度则会明显下降。同时,测试数据表明,当成核剂TMP-1的添加量为0. 05%时,弯曲模量可以达到最大值(2 253. 82 MPa),与未添加成核剂的纯树脂相比,弯曲模量提高了81. 1%。     

连续CF增强PEEK复合材料层压板的制备工艺

采用熔融浸渍法制备了连续碳纤维(CF)增强聚醚醚酮(PEEK)复合材料预浸带,并层压成型制备复合材料层压板。研究了成型温度、成型压力、成型时间、纤维含量等因素对复合材料层压板力学性能的影响。结果表明,在成型温度为370℃、成型压力为12 MPa、成型时间为70 min、纤维含量为61%的工艺条件下,连续CF增强PEEK复合材料层压板的力学性能达到最优值,弯曲强度和弯曲弹性模量分别达到(1 750.76±49.13)MPa和(107.54±6.35)GPa,层间剪切强度达到(100.04±6.88)MPa,缺口冲击强度为(84.44±1.54)k J/m2。随着冷却速率的增大,复合材料层压板的弯曲性能和层间剪切强度下降,而缺口冲击强度提高。SEM分析表明,复合材料层压板的界面粘结良好。     

Structures and properties of injection moldings of crystallization nucleator-added polypropylenes. I. Structure–property relationships

Flexural test specimens were injection-molded from polypropylenes added with 0.5 wt % of calcium carbonate, talc, p-tert- dibutyl-benzoic acid monohydroxy aluminum, or p-di-methyl-benzylidene sorbitol under cylinder temperatures of 200–;320°C. Properties such as flexural modulus, flexural strength, heat distortion temperature, Izod impact strength, hardness, and mold shrinkage and higher-order structures such as crystalline texture, crystallinity, a^*-axis-oriented component fraction, and degree of crystalline orientation were measured and structure–property relationships were studied. By the addition of crystallization nucleators, the flexural modulus, flexural strength, heat distortion temperature, hardness, and mold shrinkage were increased and Izod impact strength was decreased. The degrees of crystalline orientation such as the orientation fraction OF and c-axis orientation function f_c were increased by the addition of nucleators. The degree of the increase was higher as the crystallization temperature was higher. Close relationships were observed between some properties and the degrees of crystalline orientation.     

Process optimization of sweet potato pulp‐based biodegradable plastics using response surface methodology

Biodegradable plastics were produced from sweet potato pulp (SPP) and cationic starch (CS) or chitosan composite (CC) by compression molding and their mechanical properties were tested. A universal testing machine, Rockwell hardness tester, and Izod impact tester were used for testing the mechanical properties (flexural strength, Rockwell hardness, and Izod strength) of the plastics. A central composite second‐order design was used to study the effects of temperature, time, and moisture content on the flexural strength, Rockwell hardness, and Izod strength of SPP/CS and SPP/CC blended plastics. The flexural strength, Rockwell hardness, and Izod strength of SPP‐based plastics was 101.1–305.9 kg/cm², R29.0–R96.7, and 0.6–3.0 kg cm cm^?2, respectively. Regression analysis predicted the optimal mechanical properties (flexural strength, Rockwell hardness, and Izod strength) to be attained with a 150–160°C temperature, 15–20‐min reaction time, and 20–23% moisture content. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 423–434, 2002     

无卤阻燃增强PP/水镁石复合管材的研制

用双螺杆挤出机制备了聚丙烯/水镁石复合材料,研究了各组分及配比对复合材料性能的影响,并制备了管材。结果表明:水镁石用量为60%时,复合材料的氧指数才能达到28%以上,但冲击强度下降了近一半,拉伸强度下降了近2/3。氯化聚乙烯对聚丙烯/水镁石体系有明显的协同阻燃作用,加入5份氯化聚乙烯,其氧指数提高了2%以上,且其综合力学性能有一定提高。体系中加入β成核剂后生成了部分β晶,可提高复合材料的韧性,且对其他性能影响不大。所制备的聚丙烯/水镁石复合管材的氧指数为31.6%,维卡软化温度94.7℃,缺口冲击强度18.6kJ/m2,弯曲模量3.1GPa,弯曲强度32.3MPa,有望用作埋地高压电力电缆套管。     

无卤阻燃PP／APP／PTP／PER复合材料的力学性能

采用多聚磷酸铵/含磷三嗪环聚合物/季戊四醇(APP/PTP/PER)体系制备了阻燃聚丙烯(PP)材料,考察了PTP及其阻燃系统的用量对阻燃PP力学性能的影响。结果表明,APP/PER使PP的缺口冲击强度和弯曲模量提高,拉伸强度有所降低,断裂伸长率下降。PTP对PP的缺口冲击强度和弯曲模量影响不大,拉伸强度有所降低,断裂伸长率下降。当加入29%APP/PER/PTP时,缺口冲击强度和弯曲模量分别比纯PP提高了62.0%和14.3%,拉伸强度和断裂伸长率分别下降了13.9%和91.0%。     

Mechanical properties of blocked polyurethane/epoxy interpenetrating polymer networks

The mechanical properties of blocked polyurethane(PU)/epoxy interpenetrating polymer networks (IPNs) were studied by means of their static and damping properties. The studies of static mechanical properties of IPNs are based on tensile properties, flexural properties, hardness, and impact method. Results show that the tensile strength, flexural strength, tensile modulus, flexural modulus, and hardness of IPNs decreased with increase in blocked PU content. The impact strength of IPNs increased with increase in blocked PU content. It shows that the tensile strength, flexural strength, tensile modulus, and flexural modulus of IPNs increased with filler (CaCO₃) content to a maximum value at 5, 10, 20, and 25 phr, respectively, and then decreased. The higher the filler content, the greater the hardness of IPNs and the lower the notched Izod impact strength of IPNs. The glass transition temperatures (T_g) of IPNs were shifted inwardly compared with those of blocked PU and epoxy, which indicated that the blocked PU/epoxy IPNs showed excellent compatibility. Meanwhile, the T_g was shifted to a higher temperature with increasing filler (CaCO₃) content. The dynamic storage modulus (E′) of IPNs increased with increase in epoxy and filler content. The higher the blocked PU content, the greater the swelling ratio of IPNs and the lower the density of IPNs. The higher the filler (CaCO₃) content, the greater the density of IPNs, and the lower the swelling ratio of IPNs. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1826–1832, 2006     

多元醇与环氧树脂共混改性的研究

采用自制的聚酯多元醇对环氧树脂进行共混改性,对改性环氧树脂固化物的拉伸强度、断裂伸长率、冲击强度、剪切强度等进行了考察,同时探讨了多元醇分子量变化及加入量不同对性能的影响。结果表明,改性后的体系韧性得到了明显的提高,如冲击强度从13.2kJ/m2提高到26.3kJ/m2。室温剪切强度从24.2MPa提高到43.75MPa。     

Mechanical and thermal properties of ABS and leather waste composites

To determine the possibility of using leather waste as reinforcing filler in the thermoplastic polymer composite, acrylonitrile–butadiene–styrene (ABS) as the matrix and leather buffing powder as reinforcing filler were used to prepare a particulate reinforced composite to determine testing data for the physical, mechanical, and thermal properties of the composites, according to the filler loading in respect to thermoplastic polymer. The ABS and leather powder composites were prepared by the extrusion of ABS with 2.5, 5, 7.5, 10, 12.5, and 15 wt % of leather powder in corotating twin screw extruder. The extruded strands were cut into pellets and injection molded to make specimens. These specimens were tested for physicomechanical properties like tensile and flexural strengths, tensile and flexural modulus, Izod and charpy impact strength, abrasion resistance, Rockwell hardness, density, Heat deflection temperature (HDT) and Vicat softening point (VSP), water absorption, and thermal degradation analysis. The incorporation of leather waste powder does not affect the tensile, flexural strengths, Izod impact strength, abrasion resistance, Rockwell hardness, density, HDT and VSP values drastically. However, the tensile modulus, tensile elongation, and charpy impact strength values are reduced significantly. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3062–3066, 2006     

高流动高模量高抗冲聚丙烯复合材料的制备及性能研究

研究了弹性体（POE）、滑石粉(talc)、乙撑双硬脂酰胺（EBS）的含量对高流动、高模量、高抗冲聚丙烯（PP）复合材料的力学性能、熔体流动速率、结晶温度、热稳定性以及微观断面结构的影响。结果表明,需要25份POE才能使高流动性共聚PP发生完全脆韧转变;通过熔融共混制备PP、POE、talc复合材料（PP/POE/talc）,当复合材料的质量份数比为80∶20∶40时,制得的PP/POE/talc复合材料的熔体流动速率为22.9 g/10 min、弯曲模量为1 887.7 MPa、缺口冲击强度为31.2 kJ/m2;对比纯PP,其弯曲模量提高了102.2 %,缺口冲击强度提高了217.8 %,弯曲强度提高了2.6 %,拉伸强度降低了15.1 %;添加1份EBS能够同时提高PP/POE/talc复合材料的熔体流动速率与缺口冲击强度。     

Preparation and mechanical characterization of chicken feather/PLA composites

Green composites, a bio‐based polymer matrix is reinforced by natural fibers, are special class of bio‐composites. Interest about green composites is continuously growing because they are environment‐friendly. This study describes the preparation and mechanical characterization of green composites using polylactic acid (PLA) matrix including chicken feather fiber (CFF) as reinforcement. Extrusion and an injection molding process were used to prepare CFF/PLA composites at a controlled temperature range. CFF/PLA composites with fiber mass content of 2%, 5%, and 10% were manufactured. The effects of fiber concentration and fiber length on mechanical properties of CFF/PLA composites have been studied. Mechanical properties of composites were investigated by tensile, compression, bending, hardness, and Izod impact testing. The results of experiments indicated that Young's modulus, compressive strength, flexural modulus, and hardness of the PLA reinforced CFF composites are higher but tensile strength, elongation at break, bending strength and impact strength of them are lower than pure PLA. The results indicate that these types of composites can be used for various applications. POLYM. COMPOS., 38:837–845, 2017. © 2015 Society of Plastics Engineers