高岭土填充聚乙烯的研究

高岭土填充聚乙烯是一种新型的复合材料,本文着重考察了高岭土对聚乙烯加工性能、机械性能、阻燃性能的影响。用扫描电子显微镜观察了高岭土——聚乙烯体系的微观形态,用热分析的方法对高岭土的阻燃效果进行了研究。结果表明,高岭土填充聚乙烯,可提高材料的尺寸稳定性,耐热性、刚性和阻燃性能。并且,高岭土自身具有加工性能好,填充量大的优点,是一种值得推广应用的矿物填料。     

丁苯橡胶/高岭土纳米复合材料的性能

采用熔融共混法和乳液共混法制备了丁苯橡胶／高岭土纳米复合材料,研究了复合材料的分散性能、力学性能和热稳定性能。结果表明,高岭土在橡胶基体中具有良好的分散性。熔融共混法制备的复合材料的力学性能基本接近白炭黑填充橡胶,其热稳定性能明显优于白炭黑填充橡胶。随着纳米高岭土用量的增大,乳液共混法制备的复合材料的拉伸强度先增大后减小,且当纳米高岭土用量为40质量份时,复合材料的综合性能良好。     

纳米高岭土/橡胶复合材料的性能研究

研究纳米高岭土／橡胶（SBR，NR，BR和EPDM）复合材料的物理性能和热稳定性能，并用透射电子显微镜、X射线衍射、红外光谱和热重分析法对高岭土／橡胶复合材料进行分析。结果表明，与白炭黑／橡胶复合材料相比，纳米高岭土／橡胶复合材料回弹性、拉伸性能和热稳定性较好，撕裂强度和定伸应力稍差；高岭土片层厚度为纳米级、分散性良好、片状粒子与橡胶大分子在纳米尺度紧密结合以及纳米高岭土片层在橡胶基体中分离且定向平行排列，是复合材料具有优良物理性能和热稳定性的重要原因。     

新型硬质高岭土在橡胶中应用性能之研究

研究了经不同细度．不同制造工艺和不同改性剂处理的硬质高岭土对橡胶力学性能和工艺性能的影响。从中筛选出综台性能最住的品种．并与常用橡胶填料(发黑、白炭黑、轻质碳酸钙)作等量(60份)填充对比。结果表明．用经硬脂酸处理过的1250日高岭土填充的橡胶力学性能比填充轻质碳酸钙的高．比填充白炭黑的略低，与填充半补强炭黑的相当；而用经硬脂酸处理过的未煅烧7000目高岭土的补强性能可望进一步提高。     

不同高岭土填充PA6复合材料的性能研究

采用熔融共混法制备了尼龙6/高岭土复合材料。研究了高岭土种类对复合材料的力学性能和加工流变性能的影响。结果表明,不同高岭土的加入使尼龙6的拉伸强度、弯曲强度和弯曲模量呈现先上升后下降的趋势,而冲击韧性呈下降趋势,但降幅较小。当用量为40份时,高岭土B填充的复合材料的性能最优。尼龙6/高岭土B复合材料的流变行为表现为假塑性,高岭土的加入使非牛顿指数减小;随温度升高,非牛顿指数变大,即非牛顿性减弱。     

高岭土在橡胶中的应用性能研究

研究高岭土与炭黑N660、沉淀法白炭黑对天然橡胶(NR)补强性能的差异,并考察高岭土部分替代炭黑N660在子午线轮胎气密层胶中的应用。结果表明,高岭土对NR的补强作用优于未加偶联剂的沉淀法白炭黑,接近炭黑N660,其中改性高岭土对NR的补强效果优于普通高岭土;采用少量高岭土尤其是改性高岭土等量部分替代炭黑N660,气密层胶料拉伸强度提高,加工性能和其他物理性能变化不大。在橡胶配方中用高岭土部分替代炭黑具有可行性,可降低原材料成本,同时节能降耗。     

PP/改性高岭土复合材料的制备及性能

采用液态三元乙丙橡胶(LEPDM)对高岭土进行表面改性，然后与聚丙烯(PP)熔融共混，制得了PP/改性高岭土复合材料，采用氧指数测定仪、熔体流动速率仪(MFR)和扫描电子显微镜(SEM)等对比分析了高岭土和改性高岭土对PP力学性能、加工性能、阻燃性能和微观形貌的影响。结果表明：高岭土及改性高岭土均会改善PP的力学性能、加工性能和阻燃性能。当填料含量相同时，PP/改性高岭土复合材料的拉伸强度、缺口冲击强度和加工性能均优于PP/高岭土复合材料，PP/高岭土复合材料的阻燃性能和弹性模量均优于PP/改性高岭土复合材料。当改性高岭土质量分数为10%时，PP/改性高岭土复合材料的缺口冲击强度和MFR均达到最大，分别为12.63 kJ/m²和1.75 g/10 min。     

聚丙烯/改性高岭土复合材料的制备及性能表征

采用乙酸钾插层改性高岭土后,与十八胺共混球磨制得表面疏水的插层改性高岭土,再与聚丙烯(PP)熔融共混制得聚丙烯/改性高岭土复合材料。采用傅里叶变换红外光谱(FTIR)、X射线衍射仪(XRD)对改性高岭土进行表征;扫描电镜(SEM)、透射电镜(TEM)、拉力机和热重分析仪分别对复合材料的表面形貌、力学性能和热学性能进行测试。结果显示,插层改性后高岭土d001为1.42 nm,增加0.7 nm,插层率达到79.65%;改性高岭土片层较均匀分散在聚丙烯基体中,随着改性高岭土的添加量的增加,复合材料力学性能和热稳定性均明显改善,当改性高岭土的填充量为7%时复合材料的拉伸强度比纯PP增加34.22%,断裂伸长率增加29.33%。     

改性接枝白炭黑填充丙烯酸酯橡胶的性能研究

主要探讨了甲基丙烯酸缩水甘油酯(GMA)接枝改性的白炭黑与橡胶的作用机理及在橡胶基体中的分散性。研究了不同种类和不同用量的白炭黑对丙烯酸酯橡胶(ACM)力学性能的影响。实验结果表明:接枝GMA的白炭黑在橡胶基体中具有较好的分散性,接枝改性的白炭黑与橡胶基体具有很好的相容性,接枝GMA的白炭黑填充的ACM力学性能较好;在白炭黑质量分数为40%时,拉伸强度达到最大值10.2MPa,而断裂伸长率在白炭黑质量分数为50%时,达到最大值345%。     

聚丙烯/高岭土复合材料的结构与性能

以钛酸酯偶联剂(NDZ-105)改性的高岭土为填料、马来酸酐接枝的聚丙烯(PP-g-MAH)为相容剂,与聚丙烯(PP)熔融共混制备复合材料,测定了复合材料的力学性能,并通过X射线衍射(XRD)、红外光谱(Fr-IR)、热失重分析(TG)、扫描电镜(SEM)等手段研究其结构.结果表明,NDZ-105分子包覆到高岭土颗粒表面,有效改善了高岭土与PP基体的相容性;改性高岭土在PP基体中起到异相成核作用,并诱导PP基体产生β晶型;与纯PP及PP/未改性高岭土复合材料相比,PP/改性高岭土复合材料的拉伸强度、冲击强度、屈服强度、弹性模量、维卡软化温度及外推起始失重温度均明显提高,分别增加了7.6％、31％、21％、89.3％、8.4℃及97℃.     

Preparation and characterization of epoxy/kaolinite nanocomposites

Epoxy/kaolinite nanocomposites were prepared by adding the organically modified layered kaolinite to an epoxy resin [biphenyl phenol novolac epoxy resin (BPNE)] with 4,4′‐diamino biphenyl sulfone (DDS) as a curing agent. The dispersion state of the kaolinite within crosslinked epoxy‐resin matrix was examined by X‐ray diffraction (XRD) and transmission electron micrograph (TEM). The effects of kaolinite on thermal properties were investigated and discussed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Experimental results show that BPNE/kaolinite nanocomposites exhibit improved thermal than pure BPNE. When the kaolinite content is 5 wt %, the BPNE/kaolinite nanocomposites show the best thermal properties. These results indicate that nanocomposition is an efficient and convenient method to improve the thermal properties of BPNE. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Properties of thermally conductive silicone rubbers filled with admicellar polymerized polypyrrole-coated Al2O3 particles

Polypyrrole (PPy) nanolayers were introduced on the surface of alumina (Al₂O₃) particles via admicellar polymerization. The properties of silicone rubbers (SRs) filled with PPy-coated Al₂O₃ and pristine Al₂O₃ as thermally conductive fillers were studied and compared. The results demonstrate that the addition of PPy-coated Al₂O₃ leads to a better interfacial compatibility but lower cross-linking density of the composites than pristine Al₂O₃. The improvement in the compatibility and the decrease in the cross-linking density are paradoxes in affecting mechanical properties. The improvement in the compatibility shows a slight predominance on the strength at low-filler contents. Lower cross-linking density of modified-Al₂O₃/SR composites led to a better processing performance and a higher maximum filler loading amount than the pristine Al₂O₃/SR composites, which is beneficial to increasing the thermal conductivity and maintaining a relatively good strength. The PPy-coated Al₂O₃/SR composite with 83 wt% filler content has a thermal conductivity of 1.98 W/(m K) and a tensile strength of 2.9 MPa, and the elongation at break was 63%. Functionalized fillers by admicellar polymerization used in the fabrication of filler/SR composites not only improve the interfacial compatibility but also optimize and expand the functions of the composites, which has great significance for the production and application of thermally conductive SR in some branches of industry (automotive, electrical engineering, etc.) in the future.     

The impact of polymer matrix blends on thermal and mechanical properties of boron nitride composites

To improve mechanical and thermal properties of a hexagonal boron nitride platelet filled polymer composites, maleic anhydride was studied as a coupling agent and compatibilizer. Injection molded blends of acrylonitrile butadiene styrene (ABS), high-density polyethylene (HDPE), and maleic anhydride with boron nitride filler were tested for thermal conductivity and impact strength to determine whether adding maleic anhydride improved interfacial interactions between matrix and filler and between the polymers. Adding both HDPE and maleic anhydride to ABS as the matrix of the composite resulted in a 40% improvement in impact strength without a decrease in thermal conductivity when compared to an ABS matrix. The best combination of thermal conductivity and impact strength was using pure HDPE as the matrix material. The effective medium theory model is used to help explain how strong filler alignment helps achieve high thermal conductivity, greater than 5 W/m K for 60 wt % boron nitride. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48661.     

Electrorheological properties of kaolinite,polyindole, and polyindole/kaolinite composite suspensions

In this study, polyindole (PIN) and polyindole/kaolinite (PIN/KAO) composite were synthesized by free radical polymerization using FeCl₃ as an initiator. Average particle sizes (d₅₀) of PIN and PIN/KAO composite were determined by dynamic light scattering (DLS) as 7.2 and 6.2 μm, respectively. The samples were characterized by FTIR, elemental analysis, DSC/TGA and SEM measurements. Suspensions of KAO, PIN, and PIN/KAO composite were prepared in silicone oil (SO) and the sedimentation stabilities were determined. Electrorheological (ER) properties of these suspensions were studied as a function of dispersed phase concentration, shear rate, shear stress, and temperature; and yield stresses and excess shear stresses determined. Further, dielectric properties of KAO, PIN, and PIN/KAO composite were investigated. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Preparation and characterization of poly(vinyl alcohol) biocomposites with microalgae ash

Gasification of microalgae feedstock generates mineral ash. In this work, raw ash is produced from lipid‐extracted algal biomass of the Nannochloropsis salina strain. Prior to using it as filler for composite fabrication with poly(vinyl alcohol), raw ash (RASH) is activated with NaOH and surface modified with (3‐aminopropyl)triethoxysilane. Surface modification of activated ash (PASH) significantly improves interfacial interaction between surface‐modified ash (GASH) and polymer matrix. Higher ultimate tensile strength of PVA/GASH composites is recorded, compared with PVA/RASH and PVA/PASH. Young's modulus of biocomposites appears to increase proportionally to loading of the fillers. Thermal properties of polymeric materials of PVA with these ashes are stable. This is the first report to demonstrate the utilization of microalgal ash, the leftover after completed gasification of algal biomass, as an efficient filler for production of value‐added polymeric materials. It is proposed that microalgal ash is capable of improving the economic feasibility of microalgae‐based biorefinery. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43599.     

Influence of kenaf form and loading on the properties of kenaf‐filled polypropylene/waste tire dust composites: A comparison study

Kenaf (KNF)‐filled polypropylene/waste tire dust (PP/WTD) composites containing different KNF loadings (0, 5, 10, 15, and 20 parts per hundred parts of resin (phr)) were prepared using a Thermo Haake Polydrive internal mixer. The influence of the KNF form (KNF short fiber (KNFs) and KNF powder (KNFp)) at different KNF loadings on properties of the composites was studied. Results showed that with increasing KNF loading, the stabilization torque, tensile modulus, water absorption, and thermal properties increased for both KNFp‐ and KNFs‐filled PP/WTD composites. However, the tensile strength and elongation at break decreased by 29.2% and 53.9%, respectively, for KNFp‐filled PP/WTD composites, whereas KNFs‐filled PP/WTD composites showed a decrement of 24.5% and 63.5%, respectively. The stabilization torque, tensile strength, and tensile modulus increased by 22.4%, 6.7%, and 2.6%, respectively, for KNFs‐filled PP/WTD composites at 20 phr KNF loading. The scanning electron microscopy morphological studies on the tensile fractured surfaces revealed poor adhesion between KNFp and PP/WTD matrices as compared to KNFs and PP/WTD matrices. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40877.     

Nitrile functionalized benzoxazine/bismaleimide blends and their glass cloth reinforced laminates

A novel high‐performance resin blend composed of nitrile functionalized benzoxazine (CNBZ) and bismaleimide (4,4′‐bismaleimidodiphenyl methane) (BMI) was prepared via solvent method. Its curing behaviors, thermal properties, and mechanical properties were studied by differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR), dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), and universal testing machine, respectively. The results showed that the addition reaction between phenolic hydroxyl group and the double bond occurred except for the homopolymerization of CNBZ and BMI. When BMI content was more than 40%, the cured CNBZ/BMI blends exhibited higher glass transition temperatures (T_gs) than CNBZ and BMI homopolymers, which reached up to 334°C. Meanwhile, when BMI content was 40%, the tensile strength, flexural strength, and shearing strength reached up to 69, 235, and 12.9 MPa, respectively, which exhibited the comparable mechanical properties with BT resin. Furthermore, the glass cloth (GF) reinforced laminates based on these blends were prepared. The results showed that when BMI content was 40%, their tensile strength, flexural strength, and impact strength reached up to 334 MPa, 593 MPa, and 145 KJ m^?2, respectively. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41072.     

Rice husk powder–filled polystyrene/styrene butadiene rubber blends

Natural fibers are rich in cellulose and they are a cheap, easily renewable source of fibers with the potential for polymer reinforcement. The presence of large amounts of hydroxyl groups makes natural fibers less attractive for reinforcement of polymeric materials. Composites made from polystyrene (PS)/styrene butadiene rubber (SBR) blend and treated rice husk powder (RHP) were prepared. The RHP was treated by esterification and acetylation. A similar series of composites was also prepared using maleic anhydride–polypropylene (MA–PP) as a coupling agent. The processing behavior, mechanical properties, effect of thermooxidative ageing, and surface morphology of untreated and chemically modified RHP were studied. There was a decrease in tensile strength (except MA–PP composites), elongation at break, and Young's modulus in chemically treated RHP composites. The postreaction process during thermooxidative ageing enhanced the tensile strength and Young's modulus of the esterified and MA–PP composites. Acetylation treatment was effective in reducing the percentage of water absorption in RHP/PS–SBR composites. In general chemically treated RHP/PS–SBR composites and MA–PP showed a better matrix phase and filler distribution. However, the degree of filler–matrix interaction was mainly responsible for the improvement of mechanical properties in the composites. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3320–3332, 2004     

Thermal and mechanical properties of liquid silicone rubber composites filled with functionalized graphene oxide

To improve the thermal and mechanical properties of liquid silicone rubber (LSR) for application, the graphene oxide (GO) was proposed to reinforce the LSR. The GO was functionalized with triethoxyvinylsilane (TEVS) by dehydration reaction to improve the dispersion and compatibility in the matrix. The structure of the functionalized graphene oxide (TEVS‐GO) was evaluated by Thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectra, X‐ray diffraction (XRD), and energy dispersive X‐ray spectroscopy (EDX). It was found that the TEVS was successfully grafted on the surface of GO. The TEVS‐GO/LSR composites were prepared via in situ polymerization. The structure of the composites was verified by FTIR, XRD, and scanning electron microscopy (SEM). The thermal properties of the composites were characterized by TGA and thermal conductivity. The results showed that the 10% weight loss temperature (T₁₀) increased 16.0°C with only 0.3 wt % addition of TEVS‐GO and the thermal conductivity possessed a two‐fold increase, compared to the pure LSR. Furthermore, the mechanical properties were studied and results revealed that the TEVS‐GO/LSR composites with 0.3 wt % TEVS‐GO displayed a 2.3‐fold increase in tensile strength, a 2.79‐fold enhancement in tear strength, and a 1.97‐fold reinforcement in shear strength compared with the neat LSR. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42582.