木粉表面处理对PVC／木粉复合材料性能的影响

使用钛酸酯偶联剂、油酸酰胺、聚氨酯预聚物三种表面改性剂处理木粉并制备了PVC／木粉复合材料，研究了表面改性剂的不同种类和不同用量对复合体系性能和结构的影响。结果表明：几种木粉表面处理剂均可明显提高复合材料的力学性能，其中使用4份聚氨酯预聚体和6份油酸酰胺处理木粉表面的复合体系的力学性能较优；使用表面改性剂处理木粉，也可以明显改善复合体系的流变性能；同时扫描电镜观察也发现同样规律，体系中添加改性剂，PVC与木粉的相容性明显改善，材料性能也有所提高，但表面改性剂用量过多，也会造成木粉团聚，从而影响复合材料的性能。     

果壳粉和木粉的制备与表面处理方法的研究

以果壳和木屑为原材料,制备成不同目数果壳粉和木粉,并分别对果壳粉和木粉表面进行改性。本实验采用表面接枝马来酸酐(MAH)的果壳粉和木粉处理方法,将MAH改性后的木粉和果壳粉填加到PVC树脂基体中,通过改变MAH的用量,比较了果壳粉和木粉/PVC复合材料拉伸,抗弯性能的变化情况。复合材料的抗弯强度和拉伸强度明显提高,果壳粉和木粉填充复合材料的弯曲强度分别达到68.12 MPa和80.05 MPa,达到最大值。果壳粉与PVC的界面连接得到改善。实验结果表明:改性后的果壳粉/复合材料的拉伸性能和抗弯性能明显提高。     

PVC/木粉复合材料的性能研究

采用聚氯乙烯树脂和木粉制得PVC／木粉复合材料。研究了木粉的粒径、用量，表面处理剂的类型、用量DOP以及抗冲改性剂CPE的用量对复合材料的力学性能的影响。结果表明：当木粉的粒径为过20目筛、用量为30％表面处理剂为木粉用量的1．5％，DOP和CPE的用量为PVC的用量的10％时，所得的复合材料的综合性能最佳。     

木粉填充聚乙烯的研究

研究了木粉粒度，木粉填充量以及采用不同表面处理剂处理木粉对聚乙烯（ＰＥ）力学性能和加工性能的影响，并做了阻燃性木粉填充塑料复合材料的探索试验。     

打磨对木粉/聚乙烯复合材料射流等离子体表面处理时效性的影响

采用空气气氛的射流等离子体对木粉/聚乙烯复合材料进行表面处理,以改善胶接性能。利用接触角和胶接强度测试以及红外光谱和X-射线光电子能谱分析等方法,研究了表面打磨对复合材料等离子体表面处理时效性的影响。研究结果表明,直接等离子体处理以及打磨后再等离子体处理都可以明显提高复合材料的胶接强度,相比之下,打磨后再等离子体处理可以在复合材料表面形成更多的含氧极性基团,有利于胶接性能的改善。木粉/聚乙烯复合材料的等离子体表面处理存在一定的时效性,与直接等离子体处理的复合材料相比,随着处理试样放置时间的延长,先打磨再等离子体处理的复合材料表面接触角、含氧极性基团以及胶接强度的变化幅度更小,表现出更小的处理时效性。尽管存在处理时效性,但等离子体处理后的胶接强度仍远好于未处理的试样。     

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。     

异氰酸酯处理木粉对PVC/木粉性能的影响

采用木粉填充聚氯乙烯(PVC)基木塑复合材料,研究异氰酸酯处理木粉对PVC/木粉性能的影响.红外光谱、DMA和sEM较好地证明异氰酸酯和木粉之间的作用,结果表明:用异氰酸酯处理的木粉填充PVC,能够改善木粉与PVC之间的界面粘结作用,提高PVC/木塑复合材料的力学性能.     

木粉填充聚氯乙烯发泡体系的力学性能研究

以聚氯乙烯（PVC）为基体树脂，脂肪酸、铝酸酯偶联剂和丙烯酸烷基酯接枝聚合表面处理的木粉为增强材料制备聚氯乙烯／木粉发泡复合材料。研究了木粉的处理方法和含量以及DOP用量对复合材料力学性能、发泡性能的影响。用扫描电子显微镜（SEM）对木粉和PVC基体之间的结合界面进行了观察，发现PVC和处理木粉间形成了结合良好的界面层。     

纳米碳酸钙性质对聚氯乙烯复合材料界面及性能的影响

选择了不同的表面处理剂对纳米CaCO₃进行表面改性. 研究了不同表面处理剂对CaCO₃/PVC纳米复合材料微观结构、界面结合强度、力学性能及加工性能的影响.研究表明,钛酸酯偶联剂处理可使纳米CaCO₃颗粒在PVC基体中达到良好分散,明显改善纳米CaCO₃颗粒与PVC基体之间的界面结合,并提高其界面结合强度.力学性能和流变性能研究表明,钛酸酯处理的纳米CaCO₃填充PVC具有更高的拉伸强度、冲击强度以及更低的平衡转矩, 而且CaCO₃/PVC复合材料的冲击韧性在填充量为20%(mass)时达到最大值26.5 kJ•m^-2,是纯PVC的4倍.     

微波处理与接枝对PVC／木粉复合材料结构与性能的影响

采用经微波辐射去离子水浸润的木粉制备了PVC／木粉复合材料。研究了微波处理对PVC／木粉复合材料冲击强度、拉伸强度的影响。结果表明，与未处理木粉相比，经过微波处理后的木粉与PVC复合材料的冲击强度提高了13．79％～28．41％；拉伸强度提高了5．87％～27．14％。此外，用微波处理经丙烯酰胺水溶液浸润过的木粉而制备的PVC／木粉复合材料，力学性能又得到了进一步提升；傅里叶变换红外光谱分析表明丙烯酰胺在木粉表面发生了接枝反应；扫描电镜分析也表明，经过微波接枝反应后，木粉与PVC的相界面连续性变好，两相相容性得到了提高。     

表面接枝改性木粉及其在PVC基木塑复合材料中的应用

以硝酸铈铵为引发剂引发丙烯酸丁酯(BA)在木粉表面的接枝聚合反应.探查了其表面改性的最佳工艺;接触角数据表明木粉经接枝共聚后,其表面性质已经由亲水变为疏水;将该改性木粉填充PVC后,复合材料的力学性能得到大幅度提高,其中拉伸强度提高了7.9%,而冲击强度则提高了107.5%.     

木粉和发泡剂对PVC基木塑复合发泡材料性能的影响

以木粉、聚氯乙烯树脂、发泡剂等为原料,通过连续挤出得到发泡木塑复合材料。对木粉的热失重、复合发泡材料的泡孔形态、力学性能进行了测试。结果表明:发泡剂用量不应超过1phr;在本实验范围内,木粉粒径的减小会使发泡更容易,材料的力学性能得到改善;木粉粒径对泡孔形态和力学性能的影响有一个最佳范围,即20~80目。     

Coextruded PVC/wood‐flour composites with WPC cap layers

Wood‐plastic composites (WPCs) can absorb moisture in a humid environment owing to the hydrophilic nature of the wood, thereby making the products susceptible to microbial growth and loss of mechanical properties. In this study, rigid poly(vinyl chloride) (PVC)/wood‐flour composites (core layer) were coextruded with either unfilled rigid PVC (cap layer) or rigid PVC filled with a small amount (5–27.5%) of wood flour (composite cap layers) in order to decrease or delay the moisture uptake. The thickness of the cap layer and its composition in terms of wood flour content were the variables examined during coextrusion. Surface color, moisture absorption, and flexural properties of both coextruded and noncoextruded (control) composite samples were characterized. The experimental results indicated that both unfilled PVC and composite cap layers can be encapsulated over rigid PVC/wood‐flour composites in a coextrusion process. The moisture uptake rate was lower when a cap layer was applied in the composites, and the extent of the decrease was a strong function of the amount of wood flour in the cap layer but insensitive to cap layer thickness. Overall, coextruding PVC surface‐rich cap layers on WPCs significantly increased the flexural strength but decreased the flexural modulus as compared with those of control samples. The changes in bending properties were sensitive to both cap layer thickness and wood flour content. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers     

Manufacture of rigid PVC/wood‐flour composite foams using moisture contained in wood as foaming agent

Relatioships between the density of foamed rigid PVC/wood‐flour composites and the moisture content of the wood flour, the chemical foaming agent (CFA) content, the content of all‐acrylic foam modifier, and the extruder die temperature were determined by using a response surface model based on a four‐factor central composite design. The experimental results indicated that there is no synergistic effect between teh CFA content and the moisture content of the wood flour. Wood flour moisture could be used effectively as foaming agent in the production of rigid PVC/wood‐flour composite foams. Foam density as low as 0.4 g/cm³ was produced without the use of chemical foaming agents. However, successful foaming of rigid PVC/wood‐flour composite with moisture contained in wood flour strongly depends upon the presence of all‐acrylic foam modifier in the formulation and the extrusion die temperature. The lowest densities were achieved when the all‐acrylic foam modifier concentration was between 7 phr and 10 phr and extruder die temperature was as low as 170°C.     

Flame retardancy,antifungal efficacies,and physical–mechanical properties for wood/polymer composites containing zinc borate

This work aimed to examine flame retardancy, antifungal performance and physical–mechanical properties for silane‐treated wood–polymer composites (WPCs) containing zinc borate (ZnB). ZnB with content from 0.0 to 7.0 wt% was added to WPCs, and silane‐treated wood contents were varied. The polymers used were poly(vinyl chloride) (PVC) and high‐density polyethylene (HDPE). The decay test was performed according to the European standard EN 113. Loweporus sp., a white‐rot fungus, was used for antifungal performance evaluation. Antifungal performance was observed to decrease with wood content. Incorporation of ZnB at 1.0 wt% significantly increased the antifungal performance of WPCs. ZnB content of greater than 1.0 wt% lowered the antifungal properties of WPCs. The results suggested that the wood/PVC composite exhibited better antifungal performance than the wood/HDPE composite. The addition of wood flour to PVC and HDPE decreased flame retardancy, whereas the incorporation of ZnB retained the flame retardancy. ZnB was found to be more appropriate for wood/PVC than wood/HDPE as a result of hydrogen chloride generated from the dehydrochlorination reaction of PVC. The results indicated that the addition of ZnB did not affect the physical‐mechanical properties of neat polymers and the composites. Copyright © 2016 John Wiley & Sons, Ltd.     

PVC/WF发泡材料的性能研究

采用NaOH溶液、丙烯酸丁酯、甲基丙烯酸甲酯和硅烷偶联剂KH-550分别对木粉(WF)进行表面处理,利用傅立叶变换红外光谱仪对其进行表征,并用处理过的WF增强聚氯乙烯(PVC)树脂,经一步模压法制备PVC/WF发泡材料.对其进行力学性能、物理性能测试,比较不同表面处理方法对该发泡材料各项性能的影响.结果表明,WF经表面处理后制备的PVC/WF发泡材料性能均有所提高,其中以NaOH处理后所得复合材料综合性能最优:拉伸强度提高112%,密度从205.4 kg/m3减小到102.3 kg/m3,吸水率、吸油率和线性收缩率均有大幅度改善.     

Mold susceptibility of rigid PVC/wood‐flour composites

Rigid PVC/wood‐flour composite lumber containing either hardwood (maple) or a softwood (southern pine) wood flour at different levels of wood‐flour content was evaluated for susceptibility to fungal colonization and discoloration by using standard tests that mimicked exterior (ASTM G21) and interior (ASTM D3273) environments, respectively. In the exterior test protocol, although both types of PVC/wood‐flour composite lumber exhibited fungal colonization and discoloration, the composites containing maple exhibited greater discoloration than those containing pine. Irrespective of wood species, fungal colonization and discoloration in the composite lumber were greater at the bottom faces where they were in constant contact with moisture. The wood content range (50–100 phr) used in this study showed no effect on extent of fungal colonization and discoloration. All composites showed no discoloration in the interior test protocol. Both optical microscopy and environmental scanning electron microscopy clearly demonstrated that wood flour particulates are not completely encapsulated by the PVC matrix, so that exposed wood flour in the surface crevices of the composite lumber may serve as points of moisture sorption and staging points for fungal colonization and discoloration. J. Vinyl Addit. Technol. 10:179–186, 2004. © 2004 Society of Plastics Engineers.