改性椰壳粉/PVC复合材料的研究

用改性剂改性椰壳粉并填充到PVC中制得性能优良的椰壳粉/PVC复合材料。用SEM进行结构分析,研究了椰壳粉的热重(TG)、改性方法对复合材料力学及加工性能的影响。结果表明:改性方法对复合材料性能有较大影响,以20%HDPE-g-(GMA-co-St)塑炼改性效果较好,与纯PVC相比,改性椰壳粉/PVC复合材料的断裂拉伸强度(TSb)、断裂冲击强度(LS)、洛氏硬度(HL)、熔体指数(MI)分别提高了16.57%、61.97%、29.41%、123%。SEM观察显示,椰壳粉在PVC基体中的分散性和相容性得到改善。     

废弃椰壳粉/PVC复合材料结构和性能的研究

研究了偶联剂改性椰壳粉的种类及用量、椰壳粉的质量分数对椰壳粉/PVC复合材料性能的影响,并用扫描电镜(SEM)观察了其两相结构和断面形貌.结果表明:硅烷偶联剂KH-550在用量为2%时效果较好,拉伸强度提高了12.6%,冲击强度提高了31%;经过硅烷偶联剂KH-550改性后椰壳粉填充质量分数增大,且降低趋势较小,有效降低复合材料的成本;经过KH-550改性能较大幅度的增大复合材料的耐热变形性能;KH-550改性改善了椰壳粉纤维在PVC基体中分散性和相容性.     

改性椰壳粉／PVC复合材料结构和性能的研究

研究了偶联剂改性椰壳粉的种类及用量、椰壳粉的质量分数对椰壳粉／PVC复合材料性能的影响,并用扫描电镜（SEM）观察了拉伸断面。结果表明：硅烷偶联剂KH-550质量分数为2％时效果较好,拉伸强度提高了12．6％,冲击强度提高了30．6％;经过硅烷偶联剂KH-550改性,能增大椰壳粉填充质量分数,提高复合材料的维卡软化点温度,改善了椰壳粉纤维在PVC基体中分散性和相容性。     

竹粉用量对PVC/竹粉复合材料力学性能的影响

采用自制的聚乙烯蜡接枝马来酸酐(PEW-g-MAH)改性竹粉,制成PVC/竹粉复合材料,研究了竹粉用量对PVC/竹粉复合材料力学性能的影响。结果表明:随着竹粉用量的增加,试样力学性能总体呈现降低的趋势;添加PEW-g-MAH改性竹粉的试样力学性能要明显优于添加未改性竹粉的试样。SEM分析表明:经PEW-g-MAH处理后,竹粉与PVC树脂的相容性得到改善,可提高试样的力学性能。     

聚氯乙烯/秸秆粉木塑复合材料的性能研究

采用模压成型法制备了聚氯乙烯(PVC)/秸秆粉木塑复合材料,研究了秸秆粉含量及不同偶联剂处理对复合材料力学性能和接触角的影响。结果表明,当秸秆粉含量为40%(质量分数,下同)时,复合材料的弯曲强度最大,且在复合材料的内部,秸秆纤维相对较均匀地分布于PVC基体中,复合材料性能相对较好;经偶联剂改性的复合材料的力学性能均有所提高,经硅烷偶联剂改性的秸秆粉含量为50%的复合材料的洛氏硬度、弯曲强度均最大;且在复合材料内部,秸秆纤维更均匀地融入PVC基体中,硅烷偶联剂的改性效果较好。     

CPE对PVC/木粉复合材料动态力学性能及耐热性能的影响

为了增强聚氯乙烯(PVC)基木塑复合材料的动态力学性能,加入氯化聚乙烯(CPE)对复合材料进行改性,并探究CPE对PVC基木塑复合材料性能的影响。采用动态力学分析仪(DMA)和维卡软化温度测试仪,对加入CPE的PVC/木粉复合材料进行测试,分析CPE对PVC/木粉复合材料动态力学性能及耐热性能的影响。结果表明:CPE的加入会对PVC/木粉复合材料的动态力学性能产生重要的影响,且CPE含量约为5份时,复合材料的动态力学性能最佳;但维卡软化温度、热变形温度测试结果显示,CPE的加入降低了PVC/木粉复合材料的耐热性,且随着CPE含量的增加,复合材料的耐热性逐渐减弱。     

腰果壳粉/PVC复合材料的结构和性能

通过采用六次甲基四胺对腰果壳粉进行改性,并制备了腰果壳粉/聚氯乙烯(PVC)复合材料。研究改性前后腰果壳粉的用量对复合材料力学性能、耐水性和加工性能的影响,并用扫描电镜(SEM)观察了断面形貌。结果表明:随着不同腰果壳粉用量的增加,复合材料的拉伸强度、冲击强度、弯曲强度呈先上升后下降的趋势,当腰果壳粉用量为5～10份时最佳;添加质量分数为5%的六次甲基四胺改性腰果壳粉时,复合材料的物理力学性能、耐水性提高。     

PVC/改性废EMC粉复合材料结构和性能的研究

以电子元器件生产塑封过程中产生的废环氧模塑料(废EMC)作为填料,以模压成型的方法制备PVC/废EMC粉复合材料.研究了用硅烷偶联剂KH-550改性前后废EMC粉不同含量对复合材料力学性能的影响,用扫描电子显微镜观察了复合材料的微观结构和形貌,并研究了偶联剂的加入对复合材料耐热性能的影响.结果表明,KH-550明显提高了复合材料的力学性能,废EMC粉经改性后对复合材料起到了增强增韧作用,可相应增大填充量,有利于提高废料再利用率.KH-550的加入改善了废EMC粉和PVC基体间的界面结合性能,提高了复合材料的维卡软化温度.     

废EMC粉/PVC复合材料的结构与动态力学性能

以废环氧模塑料粉(废EMC粉)为填料,采用模压成型的方法制备了废EMC粉/PVC复合材料.利用扫描电镜(SEM)和动态热性能分析(DMA)研究了硅烷偶联剂KH-550对复合材料微观形貌和动态力学性能的影响.结果表明:硅烷偶联剂KH-550的加入,大大改善了废EMC粉和PVC之间的界面黏结强度,增强了界面之间的作用力,复合材料的储能模量和玻璃化转变温度提高,损耗模量和损耗因子峰值降低,宏观上表现出复合材料力学性能的提高.     

改性碳纳米管共沉淀处理及其在聚氯乙烯复合材料中的应用

首先采用共沉淀法制备了聚氯乙烯(PVC)/改性碳纳米管(CNTs)初产物(PVC包覆的改性CNTs粒子),然后将其与PVC经双辊塑炼及压制成型得到该初产物的PVC复合材料,并测试了该复合材料的力学性能和电性能。结果表明:随着改性CNTs用量的增加,PVC/改性CNTs复合材料的表面电阻率逐渐降低,而缺口冲击强度则先增后减,与空白样相比,当改性CNTs用量为1份时,复合材料的导电性和缺口冲击强度均有显著改善;另外改性CNTs经过共沉淀处理后,所得PVC/改性CNTs复合材料的导电性有所降低,但是改性CNTs在PVC基体中的分散性则有所改善,复合材料的缺口冲击强度明显提高。     

Thermal and dynamic mechanical behavior of poly(vinyl chloride)/wood flour composites

Thermal and dynamic mechanical behaviors of wood plastic composites made of poly vinyl chloride (PVC) and surface treated, untreated wood flour were characterized by using differential scanning calorimetry and dynamic mechanical analysis. Glass transition temperature (T_g) of PVC was slightly increased by the addition of wood flour and by wood flour surface treatments. Heat capacity differences (ΔC_p) of composites before and after glass transition were markedly reduced. PVC/wood composites exhibited smaller tan δ peaks than PVC alone, suggesting that less energy was dissipated for coordinated movements and disentanglements of PVC polymer chains in the composites. The rubbery plateaus of storage modulus (E′) curves almost disappeared for PVC/wood composites in contrast to a well defined plateau range for pure PVC. It is proposed that wood flour particles act as “physical crosslinking points” or “pinning centers” inside the PVC matrix, resulting in the absence of the rubbery plateau and high E′ above T_g. The mobility of PVC chain segments were further retarded by the presence of surface modified wood flour. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

表面处理对木粉增强PVC发泡复合板材性能的影响

研究表面处理的木粉对发泡聚氯乙烯(PVC)板材的增强改性效果。使用铝酸酯偶联剂、丙烯酸丁酯预聚物对木粉进行表面处理，将其混合到聚氯乙烯发泡板材配料中进行板材加工生产，结果表明，经处理的木粉能提高发泡PVC板材的拉伸强度和冲击强度。用铝酸酯偶联剂处理木粉的发泡板材力学性能好于用丙烯酸丁酯预聚物处理的板材；而用丙烯酸丁酯预聚物处理木粉的复合材料在流变加工性能优于用铝酸酯处理木粉的复合材料。     

竹粉用量对PVC/竹粉复合材料阻燃抑烟性能的影响

采用自制的聚乙烯蜡接枝马来酸酐对竹粉进行改性,并制备了PVC/竹粉复合材料;研究了改性竹粉用量对PVC/竹粉复合材料阻燃抑烟性能的影响.结果表明:①PVC/竹粉复合材料的氧指数随着改性竹粉用量的增加而下降;②当改性竹粉的用量为10~50份时,PVC/竹粉复合材料的垂直燃烧性能达到FV-0级,水平燃烧性能达到FH-1级;...     

Study on PVC composites containing Eugenia jambolana wood flour

This article describes the properties of composites using unplasticized PVC matrix and wood flour (obtained by crushing the bark of Eugenia jambolana) as filler. Composites were prepared by mixing PVC with varying amounts of wood flour (ranging from 10–40 phr; having particle sizes of 100–150 μm and <50μm) using two‐roll mill followed by compression molding. The effect of wood flour content and its particle size on the properties, i.e., mechanical, dynamic mechanical, and thermal was evaluated. Tensile strength, impact strength, and % elongation at break decreased with increasing amounts of wood flour. Stiffness of the composites (as determined by storage modulus) increased with increasing amounts of the filler. Modulus increased significantly when wood flour having particle size <50 μm was used. Morphological characterization (SEM) showed a uniform distribution of wood flour in the composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

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。     

PVC／木粉复合材料抗冲改性研究

用甲基丙烯酸、丙烯酸丁酯、甲基丙烯酸甲酯三元共聚物P（MAA—BA—MMA）对木粉进行预处理,再利用CPE、ACR和nano—CaCO3对PVC／木粉复合材料进行增韧改性。结果表明,木粉经P（MAA—BA—MMA）预处理后,使用ACR增韧时效果最好,其拉伸强度、弯曲强度、冲击强度和断裂伸长率分别提高了7．97％、5．26％、68．85％和571．26％。SEM结果表明,木粉预处理后再增韧,复合材料界面模糊,断面呈一定的韧性断裂特征。     

Online measurement of rheological properties of PVC/wood‐flour composites

By using a factorial design approach, this study examined the effect of the component materials on the viscoelastic properties of PVC/wood‐flour composites. Statistical analysis was performed to determine the effects of wood‐flour content, acrylic modifier content, and plasticizer content on the die swell ratio and viscosity of the composites measured online on a conical twin‐screw extrusion capillary rheometer. The viscoelastic properties of the samples also were measured using dynamic mechanical analyzer (DMA). Wood‐flour content and acrylic modifier content were the two important variables affecting the die swell ratio, whereas the addition of a low level of plasticizer did not affect this ratio. The die swell increased with the increased acrylic modifier content, but it was reduced considerably by adding wood flour into the PVC matrix. The true viscosity of neat PVC and PVC/wood‐flour composites decreased with the plasticizer content, irrespective of the acrylic modifier content. However, the addition of acrylic modifier significantly increased the viscosity of unfilled PVC, while an opposite trend was observed for the composites, owing to the differing effect of acrylic modifier on the melt elasticity and viscosity of these materials. J. Vinyl Addit. Technol. 10:121–128, 2004. © 2004 Society of Plastics Engineers.