接枝聚丙烯增容改性PP/PA合金性能的研究

用PP接枝物增容PP/PA6共混体系,观察分析了共混合金的形态结构特点,测试了共混物的力学性能.结果表明：单独加入PP-g-MAH,力学性能均呈现先升后降的趋势,峰值时拉伸强度比未加接枝物时可提高20%,弯曲强度比未加接枝物时提高了54%,冲击强度比不添加接枝物时提高了3.6%.添加PP-g-MAH对不同比例PP/PA6共混物力学性能的影响不同,固定PP-g-MAH用量为4%,PA6质量分数为30%时共混物的综合力学性能达到最好.用PP-g-MAH和PP-g-GMA两种接枝物共同作为相容剂加入到PP/PA6共混物中比单独使用一种的效果要好,拉伸、弯曲和冲击强度都得到显著的提高.由共混物的SEM照片可以看到,PP-g-MAH使分散相的粒径变小,分布均匀,界面相互作用加强,所以是PP/PA6共混物的有效增容剂.     

POE-g-MAH对PP/PA6共混体系形态结构与力学性能的影响

研究了乙烯-辛烯共聚物接枝马来酸酐(POE-g-MAH)作为相容剂对PP/PA6共混体系相容性、形态结构和宏观力学性能的影响.研究结果表明在PP/PA6共混体系中加入相容剂POE-g-MAH,不仅能够显著改善PP/PA6共混物的相容性,明显降低分散相的粒径,而且能够使PP/PA6共混物在保持较高的拉伸强度和弹性模量的同时,大幅度地提高共混物的缺口冲击强度和断裂伸长率,与纯PP相比提高幅度分别达到198.3%和778.8%.POE-g-MAH增容PP/PA6共混体系的非等温结晶行为的研究表明,PA6作为成核剂使PP的结晶温度提高,POE-g-MAH的加入能进一步促进PA6对PP基体的异相成核作用.     

PP-g-GMA的制备及其增容PP/PA6共混物的性能

通过熔融接枝反应制备了甲基丙烯酸缩水甘油酯接枝聚丙烯（PP-g-GMA）,并将其作为聚丙烯/聚酰胺6（PP/PA6）共混物的相容剂,研究了PP-g-GMA对PP/PA6共混物的力学性能及形态结构的影响。结果表明,采用滴定法测得PP-g-GMA接枝率为3.35 %;当PP-g-GMA的添加量为4 %（质量分数,下同）和8 %时,PP/PA6/PP-g-GMA共混物的拉伸强度和缺口冲击强度分别较PP/PA6共混物提高了32.4 %和60.4 %;PP-g-GMA显著改善了PP/PA6 共混物的界面相容性,是PP/PA6共混物的有效增容剂。     

PP-g-MAH对聚丙烯/尼龙6共混体的影响

研究聚丙烯接枝马来酸酐相容剂对聚丙烯／尼龙6体系的增容作用;并讨论了PP-g-MAH对PP／PA6共混物的力学性能的影响。结果表明:PP-g-MAH能有效地增强PP／PA6共混体系两相界面的相互作用,改善PP和PA6的相容性,是效果较好的相容剂。     

PP-g-MAH对PP/PA6共混物的增容作用

采用熔融接枝法,考察了单体和引发剂用量对聚丙烯(PP)/马来酸酐(MAH)接枝物接枝率的影响。将PP-g-MAH作为PP/尼龙6(PA6)共混物的增容剂,并利用SEM、XRD、DSC-TGA和万能试验机等测试手段对PP-g-MAH增容改性PP/PA6共混体系进行了研究。结果表明,PP-g-MAH接枝物对PP/PA6共混物具有良好的增容效果,PP结晶得到细化,共混物的力学性能和耐高温性能得到改善。     

聚丙烯及接枝物聚丙烯对尼龙6性能的影响

采用熔融共混法制备了聚丙烯/尼龙6(PP/PA6)和马来酸酐接枝聚丙烯/尼龙6(PP-g-MA/PA6)复合材料,用扫描电镜(SEM)和X射线衍射仪(XRD)观察表征了材料的形貌和结构,测试了材料的力学性能。研究表明:适量加入PP或PP-g-MA可提高PA6的抗冲性能,有利于PA6的α-晶型生长。与不相容PP/PA6共混物比较,PP-g-MA和PA6存在较强界面粘附,使PP-g-MA/PA6的冲击强度提高,同时保持较高拉伸、弯曲和压缩性能,PP-g-MA/PA6质量配比为10/90时,其综合性能较好。     

PE/PE-g-MAH/PA6共混物的制备及性能研究

采用熔融接枝的方法制备聚乙烯接枝马来酸酐(PE-g-MAH),将其作为PE/PA6共混物体系的相容剂,研究PE-g-MAH对PE/PA6共混物性能的影响,并探讨增容机理。结果表明,在PE/PA6共混物中加入PE-g-MAH后,共混物的力学性能得到明显的提高,当加入量在15wt%左右时,PE/PE-g-MAH/PA6共混物的拉伸强度和冲击强度达到最大值。     

PA6含量对PVC/PA6共混物形态结构与力学性能的影响

以EVA-g-MAH为相容剂,将PVC与自制的低熔点PA6共混制备了PVC/PA6共混物。通过扫描电子显微镜(SEM)和力学性能测试研究了PA6含量对PVC/PA6共混物形态结构及力学性能的影响。SEM分析结果显示:随着PA6含量的增加,PVC/PA6共混物的分散相尺寸逐渐增大,当PA6含量为10%时,共混物中分散相的分散尺寸最小为1μm;当PA6含量为50%时,共混物为两相共连续结构;当PA6含量为60%时,共混物中PA6为连续相,PVC为分散相。力学性能测试结果表明:当PA6含量为10%时,共混物的缺口冲击强度和拉伸强度都较PVC有明显提高,分别提高了约50%与30%,达到了6.29kJ/m2和60MPa。采用差示扫描量热仪(DSC)研究了PVC/PA6共混物的结晶温度,检测结果显示:PVC/PA6共混物呈现非晶结构。     

PP-g-MAH和PP-g-GMA增容PP/PA6共混体系的研究

将自制的PP—g—MAH（聚丙烯接枝马来酸酐）及PP—g—GMA（聚丙烯接枝甲基丙烯酸缩水甘油酯）作为PP／PA6共混体系的相容剂，研究了加入聚丙烯接枝物后PP，PA6塑料合金的各种力学性能及形态结构。结果表明：在PP／PA6共混物中加入PP—g—MAH后，共混物的力学性能得到明显的提高．添加PP—g—MAH对不同比例PP／PA6共混物力学性能的影响不同；用PP—g—MAH和PP—g—GMA两种接枝物共同作为相容剂加入到PP／PA6共混物中比单独使用一种的效果要好。共混物的SEM照片表明。PP—g—MAH是PP／PA6共混物的有效增容剂。     

界面作用对PP/PA6共混体系相结构与力学性能的影响

研究了两种相容剂马来酸酐接枝聚丙烯(PP-g-MAH)、马来酸酐接枝乙烯-辛烯共聚物弹性体(POE-g-MAH)对聚丙烯/尼龙6(PP/PA6)共混体系力学性能的影响.通过扫描电子显微镜(SEM)、差示扫描量热仪(DSC)分析和力学性能测试,研究了相容剂POE-g-MAH和PP-g-MAH对PP/PA6共混物相容性、形态结构和力学性能的影响.研究结果表明:两种相容剂的加入都使PP/PA6体系的相容性增加,但PP-g-MAH的加入主要表现为增强效果,而POE-g-MAH的加入主要表现为增韧效果.     

聚苯醚与尼龙6共混物的增容改性

以PPE／PA6共混物为基体,进行性能与结构的表征,对比了不同PPE／PA6比例的共混物性能以及添加增容改性树脂、增韧剂的使用效果。结果表明,增容改性树脂可使得PPE树脂粒子变得均匀,在提高共混材料的韧性的同时,改善了材料的拉伸性能;而弹性体虽可以提高PPE与PA6的共混物的冲击性能,但拉伸性能下降;添加5％增容改性树脂有助于改善玻纤增强PPE／PA6材料的力学性能。     

2,6-萘二甲酸的合成与纯化技术进展

系统综述了萘二甲酸的国内外研究进展,详细介绍了各种合成与纯化方法,并同时分析了各个方法的优缺点及经济效益.     

氨基硅油与蒙脱土协同阻燃尼龙6

通过熔融共混法制得尼龙6/纳米蒙脱土/氨基硅油复合材料,研究氨基硅油和蒙脱土的含量对共混物的力学性能和阻燃性能的影响.通过研究表明:蒙脱土的少量加入在很大程度上改善了尼龙6的力学性能和抗熔滴性能;纳米蒙脱土与氨基硅油(ASO)具有阻燃协同效应,使其极限氧指数(LOI)进一步提高.     

HDS of dibenzothiophenes and hydrogenation of tetralin over a SiO2 supported Ni-Mo-S catalyst? ?

A one-step synthesized Ni-Mo-S catalyst supported on SiO₂ was prepared and used for hydrodesulphurization (HDS) of dibenzothiophene (DBT), and 4,6-dimethyl-dibenzothiophene (4,6-DMDBT), and for hydrogenation of tetralin. The catalyst showed relatively high HDS activity with complete conversion of DBT and 4,6-DMDBT at temperature of 280 °C and a constant pressure of 435 psi. The HDS conversions of DBT and 4,6-DMDBT increased with increasing temperature and pressure, and decreasing liquid hourly space velocity (LHSV). The HDS of DBT proceeded mostly through the direct desulphurization (DDS) pathway whereas that of 4,6-DMDBT occurred mainly through the hydrogenation-desulphurization (HYD) pathway. Although the catalyst showed up to 24% hydrogenation/dehydrogenation conversion of tetralin, it had low conversion and selectivity for ring opening and contraction due to the competitive adsorption of DBT and 4,6-DMDBT and insufficient acidic sites on the catalyst surface.     

Hexaphenoxycyclotriphosphazene as FR for CFR anionic PA6 via T‐RTM: a study of mechanical and thermal properties

The production of carbon fiber reinforced (CFR) anionic polyamide 6 (APA6) plates by thermoplastic resin transfer molding (T‐RTM) processing is highly sensitive to the presence of polymer additives such as flame retardants (FRs). However, APA6 is flammable, and therefore, it is mandatory to protect the polymer matrix, especially if the produced materials are intended for aerospace applications. Typically used FR for PA6 cannot be incorporated in the T‐RTM processes. With hexaphenoxycyclotriphosphazene, an incorporable and effective FR additive for CFR APA6 was discovered. Cone calorimetry measurements indicate a char formation‐based mechanism, and the flame retardancy was further confirmed with limiting oxygen index tests, classification by UL94 (V‐0), and FAR25 tests. The influence of this FR on the thermal (thermogravimetric analysis and differential scanning calorimetry) and mechanical behavior (flexural, compressive and ultimate tensile strength, and Charpy impact tests) on CFR APA6 produced via T‐RTM processing is evaluated and indicates no interaction with the APA6; it works as a passive filler. Copyright © 2016 John Wiley & Sons, Ltd.     

重组人白细胞介素-6包含体溶解工艺研究

本文系统研究了影响大肠杆菌表达的重组人白细胞介素 6 (rhIL 6 )包含体溶解的因素 ,确定了rhIL 6包含体溶解的最佳工艺条件 ,即在 pH为 8 4的 5 0mmol/LTris HCL缓冲体系中 ,变性剂尿素和还原剂 β 基乙醇 (β ME)的浓度分别为 8mol/L和 5 0mol/L ,包含体含量为 1 0mg/mL ,在 4℃下溶解 1h。包含体溶解后蛋白含量可达到 1 3mg/mL左右 ,目标蛋白的溶解率达到 98% ,纯度为 5 0 %左右     

Studies on Impact Toughening and Thermal Properties of Nylon-6/LDPE-g-MAH Blends

Polyamide (PA)-6 is an engineering thermoplastic. It finds its application in electrical, mechanical, and automotive parts due to its very high processing and excellent barrier properties to oils. Unfortunately, Nylon-6 (Ny6) is relatively high priced, has poor impact strength, particularly when notched, and poor dimensional stability as well as poor barrier properties to moisture, which limits its applicability. On the other hand, due to low cost, low coefficient of friction, lightweight, high strength, high barrier properties to moisture, good optical properties, and ease of processing, low density polyethylene (LDPE) is an ideal material to incorporate with Polyamide-6 for film, container, and many engineering applications. The present study deals with the preparation of Nylon-6 and modified LDPE (MLDPE) blends, varying the MLDPE concentration from 0 to 50 wt%. The objective of this study is to find the effect of maleic-anhydride grafted low-density polyethylaene on various mechanical properties such as tensile, impact, and flexural properties of Nylon-6. There is a decrease in tensile and flexural properties, the notched Izod impact strength increased greatly when the MLDPE content was 20%. It includes the study the effect of MLDPE on thermal properties and morphological properties of Nylon-6. The morphology of PA/MLDPE blends showed dispersed particle in the polymeric matrix.     

新型光敏剂Ce6-PVP30的合成及其性质研究

用光谱分析的方法研究了针对国内外尚无明确报道的聚乙烯吡咯烷酮K30(简称PVP(30))与二氢卟吩e6(简称Ce6)的相互作用,文章利用低温真空冷冻干燥方法合成了二氢卟吩e6-聚乙烯吡咯烷酮PVP(30)冻干粉(简称Ce6-PVP(30)),针对国内外尚无明确报道的Ce6-PVP(30)的光漂白特性进行了分析讨论,说明光敏剂Ce6-PVP(30)光漂白特性均为光学修饰型。     

纳米碳酸钙填充尼龙6体系结晶行为的研究

采用偏光显微镜、差示扫描量热仪和广角X射线衍射仪系统地研究了纳米碳酸钙(n-CaCO3)粒子填充聚酰胺6(PA6)体系的结晶行为。结果表明,n-CaCO3粒子的引入不仅使PA6材料变为两相结构,而且使其结晶行为发生了改变;n-CaCO3粒子对PA6等温结晶行为影响较大,球晶尺寸大小及球晶形态发生了很大变化;n-CaCO3粒子不仅具有异相成核剂的作用,而且能引发PA6产生新的晶型,且这种成核作用具有逾渗行为。     

Surface modification of carbon nanofibers via deposition of an ultrathin coating of plasma‐polymerized poly(acrylic acid) and its effect on the properties of polyamide 6/CNF nanocomposites

Carbon nanofibers (CNFs) were coated with an ultrathin layer of poly(acrylic acid) (PAA) via plasma polymerization. The effect of the plasma reactor parameters on the extent of the CNF modification was studied. SEM micrographs showed that surface roughness increased with the plasma treatment. The thickness of the ultrathin PAA layer deposited on the CNF was determined by STEM to be ca. 8 nm. Untreated and treated CNF were melt‐mixed with polyamide 6 (PA6) in a Brabender mixing chamber to obtain PA6/CNF nanocomposites. The effect of the plasma treatment on the dispersion and compatibility was examined and found to improve markedly. Fractured tensile specimens showed that the CNF seemed to be completely embedded in the polymer matrix, indicating high compatibility between the PA6 and the PAA‐coated CNF. Tensile stress and tensile modulus of PA6 nanocomposites with treated CNF were found to increase by 30 and 48%, respectively, when compared with those with untreated CNF. However, the increase in tensile stress and modulus with respect to pure PA6 was 52 and 88%, respectively. Finally, XRD showed that the CNF induce the formation of the α (alpha)‐crystalline phase in PA6. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009