超支化分散剂对聚丙烯/玻璃纤维/硅灰石复合材料性能的影响

通过改变超支化分散剂DZHA-17在聚丙烯/玻璃纤维/硅灰石复合材料中的用量,考察了分散剂对复合材料加工性能、力学性能、表观性能以及分散性的影响。结果表明:随着分散剂用量的增加,复合材料的加工性能、力学性能、表观性能和分散性明显提高。当分散剂用量为1份时,复合材料的熔体流动速率提高了3.5倍,挤出机扭矩和电流分别降低到6.5 N·m和36 A,断裂伸长率、缺口冲击强度和60°光泽度也明显提高。聚丙烯/玻璃纤维/硅灰石复合材料的力学性能、表观性能与其微观结构息息相关。     

界面对PE–LLD/Al（OH）3复合材料性能影响

制备了丙烯酸(AA)接枝线型低密度聚乙烯(PE–LLD)(PE–g–AA)高分子偶联剂,并将其用于改性PE–LLD/Al(OH)3复合材料。研究了PE–g–AA对PE–LLD/Al(OH)3复合材料的微观结构、力学性能、流变行为、电气绝缘性能的影响,并探讨了复合材料力学性能、电气绝缘性能和界面微观结构之间的关系。研究结果表明,PE–g–AA偶联剂显著改善了Al(OH)3填料与PE–LLD基体之间的界面作用机制,不但提高了复合材料的拉伸和冲击强度,而且增加了复合材料的断裂伸长率。另外,PE–g–AA提高了Al(OH)3在聚合物基体的分散性并作为绝缘层减少了填料之间的相互接触,因而获得的复合材料的电气绝缘性能在低偶联剂的掺量下大幅提升,达到电气绝缘性能要求。     

偶联剂对聚丁烯–1/碳酸钙复合材料性能的影响

采用硅烷、铝酸酯和钛酸酯偶联剂对碳酸钙进行表面处理,并以聚丁烯–1为基体制备了聚丁烯–1/碳酸钙复合材料,研究了这3种偶联剂对复合材料性能的影响。结果表明,钛酸酯和铝酸酯偶联剂对碳酸钙改性的效果最好,其中铝酸酯偶联剂改性的碳酸钙接触角最大,对复合材料的增韧效果最明显,当铝酸酯偶联剂改性的用量为碳酸钙的1.5%时,改性后的碳酸钙接触角可达162.4°,相应的复合材料缺口冲击强度由未改性时的21.5 k J/m2提高至31.7 k J/m2。对铝酸酯偶联剂改性碳酸钙填充的复合材料的结晶性能及微观结构进行了分析与表征,发现铝酸酯偶联剂改性碳酸钙能够提高聚丁烯–1的结晶度,在基体内形成紧密堆积的细小球晶;铝酸酯偶联剂改性碳酸钙在聚丁烯–1中的分散性较佳,无明显团聚现象,与聚丁烯–1界面结合能力强,能够吸收形变功,提高复合材料的韧性。     

SML超分散剂改性PVC/nanoCaCO_3复合材料的性能研究

采用自制合成的SML超分散剂填充改性PVC/nanoCaCO3复合材料,并通过扫描电子显微镜(SEM)和转矩流变仪检测了nanoCaCO3改性前后的沉降体积、在PVC基体中的分散性以及PVC/nanoCaCO3复合材料的力学性能和加工流变性。结果表明:SML超分散剂改性后的nanoCaCO3粉体的沉降体积增大,在PVC基体中的分散性也明显提高;此外SML超分散剂的使用能显著增加复合材料的力学性能,减少加工塑化时间,降低扭矩。     

加工助剂对PVC木塑复合材料性能的影响

研究了4种新型加工助剂对聚氯乙烯(PVC)木塑复合材料的加工特性和物理力学性能的影响,并利用扫描电子显微镜(SEM)研究复合材料的冲击断面。结果表明,以不饱和芳香族碳氢化合物、脂肪烃树脂为主要组分的加工助剂,能够提高木粉在PVC基体中的分散性,改善木粉与PVC的相容性,从而明显提高PVC木塑材料的力学性能和加工性能;以钙皂和饱和脂肪酸酰胺混合物、脂肪醇和脂肪酸酯的混合物为主要组分的加工助剂,对木粉的分散性和复合材料的加工性能有一定的改善,但其用量较大时对复合材料的力学性能有不利影响。     

HDPE/层状硅酸盐复合材料阻隔性能研究

研究了不同层状硅酸盐包括普通蒙脱土、云母以及有机化蒙脱土对HDPE／层状硅酸盐复合材料的阻隔性能影响。结果表明：HDPE／云母(质量配比100／30)共混体系中云母作为分散相提高复合材料的阻隔性能最明显，40份分散剂TXT的加入显著提高复合材料的阻隔性能达到15倍，层状硅酸盐改进了复合材料的加工性能。     

沸石/天然橡胶复合材料的制备及其性能研究

以湿法混炼工艺为主要研究对象,分别采用湿法和干法制备了沸石/天然橡胶复合材料,研究了沸石用量对复合材料加工性能、动态性能和物理机械性能的影响。结果表明,基于湿法工艺制备的复合材料,其综合性能以及沸石在其中的分散性明显优于干法,当沸石用量为10份时,复合材料的物理机械性能较好;橡胶加工分析仪测试表明,小应变下,相对于干法混炼胶胶料,湿法混炼胶胶料的黏弹性高、弹性低、加工性能好。     

加工方式对PP/EAA/LDH复合材料性能影响

进行了聚丙烯(PP)、乙烯–丙烯酸共聚物(EAA)及水滑石(LDH)复合材料改性一体化研究,并研究了一次熔融挤出加工法和二次熔融挤出加工法对PP复合材料性能的影响。X射线多晶衍射、透射电子显微镜分析表明:两种加工方法制备的复合材料中EAA均插层和剥离了LDH,改善了LDH在PP基体中分散性,并且一次挤出加工效果优于二次挤出加工效果;热失重分析表明,两种加工方式均提高了复合材料的热稳定性能;静态力学性能测试表明:一次挤出加工制备的复合材料PP1的拉伸强度、拉伸弹性模量和缺口冲击强度均高于二次挤出加工制备的复合材料PP2。实验表明一次熔融挤出加工方法对复合材料中LDH插层和剥离效果以及LDH在PP基体中分散效果优于二次熔融挤出加工。     

氧化石墨烯/氯丁橡胶复合材料的制备与性能研究

采用乳液复合法制备氧化石墨烯(GO)/氯丁橡胶(CR)复合材料,并对其性能进行研究。结果表明:GO在CR胶料中具有良好的分散性并可改善其他无机填料的分散性,GO的加入可以明显改善CR胶料的加工安全性,提高CR硫化胶的物理性能、储能模量和耐磨性能;当GO用量为5份时,GO/CR复合材料的综合性能最佳。     

预处理棉短纤维/EPDM复合材料的性能研究

采用一种含醚键和羟基等多官能团氟硅化合物(加工助荆M)和一种脂肪酸酯磺酸盐化合物(分散剂FJ)分别预处理废旧棉短纤维(SCF),并研究预处理SCF对SCF/EPDM复合材料的硫化特性和物理性能的影响.结果表明,适量的加工助剂M或分散剂FJ均可改善SCF在EPDM中的分散性,而对胶料的硫化特性影响不大;加工助剂M能增强SCF与EPDM的界面粘合,从而提高复合材料的撕裂强度和拉断伸长率.     

ABS/膨胀蛭石复合材料性能的研究

以ABS接枝马来酸酐(ABS-g-MAH)为相容剂,通过双辊加工制备ABS/膨胀蛭石(EVMT)复合材料,研究了膨胀蛭石和相容剂的用量对复合材料性能的影响,并用热重分析仪(TGA)对复合材料的热行为进行了表征,采用电子扫描显微镜观察了复合材料内部的微观结构。实验结果表明:当ABS-g-MAH用量为9 phr、膨胀蛭石用量为15 phr时,复合材料综合性能较好。适量相容剂的加入,有利于改善ABS树脂与膨胀蛭石两相的相容性。     

复合分散体系对聚氯乙烯树脂颗粒特性的影响

以三氯乙烯模拟氯乙烯(VC),考查聚乙烯醇(KH20)/羟丙基甲基纤维素(60SH50)复合分散剂的分散能力和保胶能力,发现分散能力和保胶能力均随分散剂用量的增加而提高;复合分散剂中KH20比例增大,分散能力下降而保胶能力增强。以此为基础进行VC悬浮聚合,研究分散剂对聚氯乙烯(PVC)树脂颗粒特性的影响。发现适量的分散剂可同时提高PVC树脂的表观密度和增塑剂吸收量;增大KH20的比例可提高PVC树脂的表观密度,同时使粒度分布变窄,但是增塑剂吸收量有所下降。     

Properties of Porous Si3N4/BN Composites Fabricated by RBSN Technique

Reaction bonding of silicon nitride (RBSN) technique combined with slip-casting shaping process was used to fabricate porous Si₃N₄/BN ceramic composites. Si/BN slurry with chemical stability, good dispersibility, and viscosity was prepared using glycerol trioleate (GTO) covering on Si surface and poly(acrylic acid) (PAA) as dispersant. The hydrolysis of Si was strongly prevented by GTO coating. The dispersibility of covered Si and BN suspensions were improved by PAA dispersant. Twenty volume percent covered Si/BN slurries with low viscosity were successfully casted. The cast bodies were dried at room temperature, debindered at 750°C and nitrided below 1450°C. The nitrided samples mainly consist of α-Si₃N₄, β-Si₃N₄, and h-BN. The composites exhibit homogeneous microstructure consisting of faceted particles, α-Si₃N₄ nanowires and a large amount of pores. The porosity is 52.64% and the pore size is in the range of 60–300 nm. The composites show compressive strength of 16.6±1.5 MPa. The dielectric constant of the composite is about 3.1 and the dielectric loss is below 0.5% under different frequencies.     

不同分散剂对复掺GO/CNFs水泥基复合材料力学和导电性能的影响

新型碳纳米材料氧化石墨烯(GO)和纳米碳纤维(CNFs)在分散性良好的前提下可用于改善传统水泥基材料的性能。采用聚羧酸减水剂(PCs)、十二烷基硫酸钠(SDS)、十二烷基苯磺酸钠(SDBS)3种不同分散剂对复合GO和CNFs在水泥基材料中进行分散,研究分散剂种类对复掺GO/CNFs水泥基复合材料的力学及导电性能的影响,并通过扫描电子显微镜(SEM)对不同分散剂制备的复掺GO/CNFs水泥基试件的微观结构进行分析。结果表明:当单独使用PCs作为分散剂时,在质量分数0.05%GO和0.5%CNFs掺量下,试件的抗压强度达到最大(70.1 MPa);在0.05%GO和0.3%CNFs掺量下,试件的电阻率最小(112.65 Ω·m),且在加载条件下表现出良好的电阻率-应力变化响应。而采用SDS、SDBS两种离子型分散剂时,在GO/CNFs混合分散液的配制和试件制备过程中均会产生大量绵密且难以排出的气泡,使得水泥基复合材料的内部结构疏松,抗压强度降低,电阻率变大,导电性能下降。使用PCs单独分散的GO/CNFs水泥基试件表面水化产物结构致密,而采用SDS分散时水泥基试件微观结构疏松,且仅在100倍下即可观察到表面存在大量孔隙,因此使用PCs分散GO/CNFs对水泥基复合材料性能改善的效果最好。     

The effects of glutamine palmitic acid content on properties of high density polyethylene/silica composites

In this study, Glut Palmitate (GP) as the compatibilizer in silica filled high density polyethylene (HDPE) composites was synthesized from Glutamine and Palmitic acid. GP with varied content (0.5, 1, 2, and 3 phr) were then added in the composites to evaluate its effect on the mechanical properties, water absorption, chemical bonding, and surface morphology. The findings of this study showed that GP achieved its function as a compatibilizer by enhancing the adhesion between HDPE and silica through the formation of hydrogen bonding as investigated by Fourier transform infra‐red as well as good interaction on interface morphology observed in scanning electron microscopy micrograph. The mechanical properties showed that the tensile strength, elongation at break, flexural strength, and impact properties of composites had optimum value at 1 phr and the modulus of the composite increased with the addition of GP. Meanwhile, the addition of 2 phr of GP in composites reduced water absorption by 33% in the composite compared to the control composites. J. VINYL ADDIT. TECHNOL., 24:217–223, 2018. © 2016 Society of Plastics Engineers     

无卤阻燃聚丙烯复合材料的研究

采用添加分散剂与红磷改善氢氧化镁-聚丙烯阻燃体系的力学性能、熔体流动性及燃烧性能。结果表明,分散剂的加入改善了氢氧化镁的分散性,有效地提高了材料的机械性能;PP／Mg（OH）2／红磷体系的阻燃性能随红磷用量增加而提高,说明Mg（OH）2与红磷复配具有良好的阻燃效果。     

Effect of flame-retardant melamine and dispersants on the mechanical,thermal, and foaming properties of flexible polyurethane foam

The objective of this study was to investigate the effect of adding flame-retardant melamine and five different dispersants on the precipitation, foaming, mechanical, and thermal properties of flexible polyurethane foam (FPUF). Precipitation experiments were conducted to analyze the effect of dispersant on the separation of flame retardant and polyol, and the foaming characteristics of polyurethane (PU) foam after adding dispersant were analyzed. The effect of adding a dispersant on mechanical strength was characterized by measuring tensile strength, tearing strength, and hardness, and scanning electron microscopy analysis was performed to analyze morphological characteristics. Thermogravimetric analysis (TGA) was performed to analyze the thermal properties of PU foam. A horizontal flame test, limiting oxygen index test, and cone calorimeter tests were conducted to examine the flame retardancy of PU foam with flame retardant melamine and dispersant added. The dispersant ANTI-TERRA-U is a solution of a salt of unsaturated polyamine amides and low-molecular acidic polyesters. And, the dispersant BYK-220S is a solution of a low molecular weight, unsaturated acidic polycarboxylic acid polyester with a polysiloxane copolymer. The dispersants ANTI-TERRA-U and BYK-220S improved the density, tensile strength, tear strength, and hardness of FPUF. TGA of the top and bottom portions of the foam showed less weight difference for samples containing dispersants, indicating better homogeneity due to improved dispersibility. Therefore, we conclude that dispersants are beneficial additives to improve the mechanical properties and dispersibility of PU foam.     

Preparation and characterization of poly(styrene butylacrylate) latex/nano‐ZnO nanocomposites

Poly(styrene butylacrylate) latex/nano‐ZnO composites were prepared by blending poly(styrene butylacrylate) latex with a water slurry of nano‐ZnO particles, and the effects of certain parameters, such as particle size, dispersant type, dispersing time and others, on the dispersibility, mechanical properties, ultraviolet (UV) shielding and near infrared (NIR) shielding were investigated with transmission electron microscopy (TEM), an Instron testing machine, dynamic mechanical analysis and ultraviolet‐visible‐near infrared (UV‐VIS‐NIR) spectrophotometry. TEM observation showed that dispersants with long chains are better than those with short chains at enhancing the dispersibility of nano‐ZnO particles in a matrix; extending dispersing time also improves the dispersibility of nano‐ZnO particles in a matrix. Instron tests showed that the nanocomposite polymers embedded with nano‐ZnO particles had much higher tensile strength than the corresponding composite polymers with micro‐ZnO particles. As the nano‐ZnO content increased, the temperature of glass transition (T_g) of the nanocomposite polymer embedded with 60 nm ZnO particles first increased then decreased, but 100 nm ZnO and micro‐ZnO particles seemed to have no influence on the T_g of the composite polymers. The better dispersibility of nano‐ZnO particles resulted in higher T_g values. Increasing nano‐ZnO content or dispersibility could enhance the UV shielding properties of the nanocomposite polymers, and 60 nm ZnO particles could more effectively shield UV rays than 100 nm ZnO particles. Micro‐ZnO particles basically had no effect on the UV absorbance of the composite polymers. A blue‐shift phenomenon was observed at 365 nm when nano‐ZnO particles were present in the nanocomposite polymers. NIR analysis indicated that as nano‐ZnO content increased, the NIR shielding of the nanocomposite polymers increased, but the NIR shielding properties seemed to be more influenced by particle size than by the nano‐effect. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1923–1931, 2003     

PP／纳米CaCO3分散体系的研究

本文研究了不同的分散剂对PP／纳米CaCO3体系的分散效果,以及加工工艺条件对该体系的影响,结果表明：超分散剂CH－1A对纳米CaCO3有显著的分散作用,使体系的冲击强度有了大幅度提高。在使PP完全塑化的前提下,超分散剂CH－1A使纳米CaCO3在PP中随转速的其分散效果也提高,使体系具有较好的加工性能。     

增大白炭黑在工程机械轮胎胎面胶中用量的研究

采用脂肪酸锌皂酯、脂肪酸锌皂和混合酸锌皂3种分散剂,将白炭黑在天然橡胶(NR)和NR/丁苯橡胶(SBR)工程机械轮胎胎面胶中的白炭黑用量增大至25份,考察3种分散剂对胶料性能的影响。结果表明:使用硅烷偶联剂的同时适当添加分散剂,可以增大工程机械轮胎胎面胶中白炭黑用量,提高胶料硫化速度、改善胶料的加工性能和物理性能、明显降低胶料的生热,延长轮胎使用寿命。