酚醛改性对玻纤增强聚酰胺66复合材料耐湿性的影响

采用熔融共混法制备了线型酚醛树脂(LPF)改性的玻纤增强聚酰胺66(PA66/GF)复合材料,研究了LPF对PA66/GF复合材料吸水性、力学性能以及耐湿性的影响。结果表明:随着LPF用量的增加,改性增强PA66复合材料PA66/GF/LPF的吸水率明显降低;同时复合材料的拉伸强度略有提升,但缺口冲击强度则有所下降。另外同改性前(PA66/GF)相比,改性复合材料(PA66/GF/LPF)的耐湿性明显提升,调湿处理后材料的力学性能基本保持稳定,其中当LPF用量为4%且调湿处理10天后,复合材料的拉伸强度保持率达到82.2%,同时冲击强度变化率仅为18.6%。     

碳纤维的表面改性对导热顺丁橡胶性能的影响

研究了碳纤维的表面改性方法对碳纤维/顺丁橡胶(BR)复合材料的硫化特性、门尼粘度、导热性能和力学性能的影响.实验结果表明,碳纤维/顺丁橡胶复合材料与顺丁橡胶空白样相比,其硫化速度、导热系数与力学性能都有明显的提高.而碳纤维的表面改性对碳纤维/顺丁橡胶复合材料的硫化特性数据、门尼粘度和导热系数影响并不明显,加入碳纤维后的未改性的碳纤维/顺丁橡胶复合材料的导热性能最佳,其导热系数为0.527 W/(m·K),为顺丁橡胶空白样的1.7倍;经过高温氧化后碳纤维填充复合材料力学性能有所提高,其拉伸强度为2.39 MPa.     

木质素酚醛树脂/丁苯橡胶复合材料的研究

以木质素部分替代苯酚合成木质素酚醛树脂(LPF),制备LPF/丁苯橡胶(SBR)复合材料,并对其形态结构、物理性能和热稳定性进行研究。结果表明:LPF(木质素/苯酚用量比30/70)/SBR复合材料出现相分离,当LPF用量大于25份时,LPF与SBR相互穿插,形成互穿网络结构。加入LPF可以改善复合材料的物理性能,当LPF中木质素/苯酚用量比为30/70、LPF用量为25份时,LPF/SBR复合材料的综合性能最佳。与SBR硫化胶相比,LPF/SBR复合材料质量损失率为5%时的温度降低,质量损失率为50%时的温度升高,质量保持率增大。     

环氧树脂增强天然橡胶/顺丁橡胶并用胶的性能

采用低相对分子质量的液体环氧树脂(EP)与固化剂混合作为增强体的前驱体,比较了其填充天然橡胶(NR)、顺丁橡胶(BR)及两者并用胶的物理机械性能,考察了EP用量对并用胶及炭黑增强并用胶物理机械性能的影响,并通过扫描电子显微镜表征了填充后的NR、BR及并用胶的微观相态结构。结果表明,EP的加入均可提高NR、BR、NR/BR并用胶的物理机械性能,其中并用胶的拉伸强度提高幅度最大;当EP用量约为24份时,NR/BR并用胶的综合性能最佳;EP可以提高炭黑增强NR/BR并用胶的物理机械性能,但提高幅度不大;EP在NR/BR并用胶中呈现规整的圆球形状,直径为1.0～2.5μm。     

碳纤维对顺丁橡胶导热性能的影响

研究碳纤维用量对碳纤维/顺丁橡胶(BR)复合材料性能的影响。结果表明:随着碳纤维用量的增大,碳纤维/BR复合材料的MH和门尼粘度增大,加工性能下降;热导率明显增大,导热性能提高;邵尔A型硬度和拉伸强度逐渐增大,拉断伸长率、拉断永久变形和撕裂强度均先增大后减小。     

有机蒙脱土对三元共混胎面胶（NR／BR／SBR）结构与性能的影响

采用机械共混法制备了天然橡胶（NR）／顺丁橡胶（BR）／丁苯橡胶（sBR）／有机蒙脱土（OMMT）复合材料;用X射线衍射（xRD）和扫描电镜（SEM）对复合材料的结构进行了表征,并研究了OMMT对复合材料的物理机械性能、硫化性能、热稳定性能的影响。结果表明,该复合材料为插层型复合材料,添加5phrOMMT有利于提高复合材料力学性能、耐磨性能、热稳定性能,促进硫化,降低最低扭矩。     

BR/SEBS硫化胶的制备与性能研究

为拓宽顺丁橡胶(BR)的更广泛的应用,开发现代高性能顺丁橡胶复合材料,本文并用氢化SBS(SEBS)改善BR的抗拉强度和撕裂强度,研究了SEBS含量变化对BR/SEBS并用胶性能的影响。结果表明:BR/SEBS混炼胶的正硫化时间减少,交联密度下降,门尼黏度在SEBS含量为20份时最低,相应的BR/SEBS硫化胶的抗拉强度和撕裂强度最佳,分别是BR硫化胶的1.8倍和1.5倍;经过热空气老化,BR及BR/SEBS硫化胶的抗拉强度和撕裂强度均下降,但SEBS含量高于20份时,老化后的BR/SEBS硫化胶的抗拉强度和撕裂强度高于未老化的BR硫化胶。     

改性煅烧高岭土在车钩支撑装置用橡胶材料中的应用与性能研究

制备改性煅烧高岭土/炭黑/天然橡胶(NR)/顺丁橡胶(BR)/三元乙丙橡胶(EPDM)复合材料,并对其性能进行研究。结果表明:改性煅烧高岭土对NR/BR/EPDM并用胶具有一定的补强作用,添加适量改性煅烧高岭土可使复合材料具有良好的拉伸强度、电绝缘性能和耐热老化性能;以复合材料制备的动车组车钩支撑装置具有良好的刚度和耐压性能以及较长的使用寿命。     

硫化体系加料方式对天然橡胶/顺丁橡胶并用胶性能的影响

研究硫化体系加料方式对天然橡胶(NR)/顺丁橡胶(BR)并用胶性能的影响。结果表明:NR/BR并用胶的撕裂强度受硫化体系加料方式影响较大,邵尔A型硬度、拉伸强度和拉断伸长率对硫化体系的加料方式容忍度较高;当氧化锌、硬脂酸和硫黄全部加入BR相中时,NR/BR并用胶的耐磨性能好且大应变下的动态损耗低,综合性能较好。     

混炼工艺对炭黑/氯丁橡胶/顺丁橡胶复合材料性能的影响

以氯丁橡胶(CR)/顺丁橡胶(BR)并用胶为基体材料、炭黑为补强填料制备炭黑/CR/BR复合材料,探讨混炼工艺对复合材料性能的影响。结果表明:薄通5次时配合剂在CR/BR并用胶中分散良好;采用先将炭黑混入BR相中再与CR共混的混炼工艺可以提高炭黑的分散性,且炭黑/CR/BR复合材料的硫化特性和物理性能较好。     

Sequential interpenetrating polymer network based on styrene butadiene rubber and polyalkyl methacrylates

A series of sequential interpenetrating polymer network (IPNs) based on styrene butadiene rubber (SBR) and polyalkyl (methyl, ethyl, and butyl) methacrylates have been prepared by using tetraethylene glycol dimethacrylate as crosslinker. The IPNs were characterized by infrared spectrophotometer, dynamic mechanical analyzer, thermogravimetric analyzer, and swelling study. IPNs have exhibited higher tensile properties compared with pure SBR. IPNs based on PMMA have shown higher tensile strength compared with others. Dynamic mechanical analysis has shown that the IPNs have superior dynamic properties than SBR. Because of IPN formation, tan δ peak shifted inward between SBR and acrylates. Although the magnitude of tan δ decreased, the peaks were broadened because of micro heterogeneous phase separation. At higher concentration of methacrylate, splitting in tan δ peak was noticed because of phase separation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1120–1126, 2007     

Dynamic mechanical properties of semi‐interpenetrating polymer network‐based on nitrile rubber and poly(methyl methacrylate‐co‐butyl acrylate)

In this article, semi‐interpenetrating polymer network (Semi‐IPNs) based on nitrile rubber (NBR) and poly(methyl methacrylate‐co‐butyl acrylate) (P(MMA‐BA)) were synthesized. The structure and damping properties of the prepared Semi‐IPNs blends were characterized and by fourier transform infrared spectrum (FTIR), dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), thermogravimetric analysis (TGA/DTG), and tensile mechanical properties. The results showed that interpenetrating network based on P(MMA‐BA) and NBR was successfully obtained, which showed the improved thermal stability compared to NBR/P(MMA‐BA)‐based two‐roll mill blends. Furthermore, Semi‐IPNs showed significantly better the dynamic mechanical properties than that of the two‐roll mill system. With the increasing feed ratio of BA and MMA during the preparation of Semi‐IPNs, the loss peak position for P(MMA‐BA) in NBR/PMMA IPNs shifted to a lower temperature from 20°C to ?17°C, and when NBR in Semi‐IPNs was accounted for 40 wt %, the dynamic mechanical thermal analysis showed that much more advanced damping material with wider temperature range (?30°C < T < 80°C) as tan δ > 0.45 can be achieved. Therefore, it was expected as a promising way to obtain the excellent damping materials with good oil‐resisted properties according the Semi‐IPNs system. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40217.     

Semi‐ and full‐interpenetrating polymer networks based on polyurethane produced from canola oil and poly(methyl methacrylate)

Semi‐ and full‐interpenetrating polymer networks (IPNs) were prepared using polyurethane (PUR) produced from a canola oil‐based polyol with primary terminal functional groups and poly(methyl methacrylate) (PMMA). The properties of the material were studied and compared using dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and tensile measurements. The morphology of the IPNs was investigated using atomic force microscopy (AFM). Semi‐IPNs demonstrated different thermal mechanical properties, mechanical properties, phase behavior, and morphology from full IPNs. Both types of IPNs studied are two‐phase systems with incomplete phase separation. However, the extent of phase separation is significantly more advanced in the semi‐IPNs compared with the full IPNs. All the semi‐IPNs exhibited higher values of elongation at break for all proportions of acrylate to polyurethane compared with the corresponding full IPNs. These differences are mainly due to the fact that in the case of semi‐IPNs, one of the constituting polymers remains linear, so that it exhibits a loosely packed network and relatively high mobility, whereas in the case of full IPNs, there is a higher degree of crosslinking, which restricts the mobility of the chains. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

NR/BR/OMMT纳米复合材料的结构与性能研究及其在轮胎胎面胶中的应用

采用机械混炼法制备了天然橡胶/顺丁橡胶/有机蒙脱土(NR/BR/OMMT)纳米复合材料,并对复合材料的结构与性能进行了表征。OMMT可明显提高橡胶基体的耐油性能和物理机械性能,降低混炼胶的焦烧时间(Ts)和正硫化时间(T90),起到了促进硫化作用。轮胎胎面胶配合显示,OMMT与炭黑并用补强NR/BR共混胶,明显改善其力学性能与耐磨耗性能。     

Morphology,mechanical properties,and failure topography of semi‐interpenetrating polymer networks based on natural rubber and polystyrene

Semi‐interpenetrating networks (semi‐IPNs) were prepared from natural rubber (NR) and polystyrene (PS) by the sequential method. In these semi‐IPNs the NR phase was crosslinked while the PS phase was uncrosslinked. Different initiating systems such as dicumyl peroxide (DCP), benzoyl peroxide (BPO), and the azobisisobutyronitrile (AIBN) system were used for polymerizing the PS phase. The blend ratio was varied by controlling the swelling of NR in the styrene monomer. The mechanical properties of the semi‐IPNs, namely, density, tensile strength, tear strength, elongation at break, tension set, tensile set, impact strength, and hardness, were determined. The morphology of different IPNs was studied using scanning electron microscopy. A compact morphology with a homogeneous phase distribution was observed in the semi‐IPNs. The properties of the semi‐IPN do not change much with the initiating system. However, in most cases, the DCP initiating system showed slightly superior performance. The tensile and tear‐strength values of the IPNs were found to increase with increasing plastomer content. The crosslink density of the semi‐IPNs also increased with increase in the polystyrene content. The experimental values were compared with theoretical models such as series, parallel, Halpin Tsai, Coran, Takayanaki, Kerner, and Kunori. The tensile and tear‐fracture surfaces were examined using a scanning electron microscope. The fracture patterns were correlated with the strength and nature of the failure. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 2327–2344, 2000     

顺丁橡胶对硅橡胶/丙烯酸酯橡胶并用胶的增容作用

采用偏光显微镜、差示扫描量热仪以及力学性能、热老化性能测试手段,研究了顺丁橡胶(BR)增容的甲基乙烯基硅橡胶(MVQ)/丙烯酸酯橡胶(ACM)共混体系的并用比(质量比)、硫化工艺参数以及BR的加入对并用胶力学性能、耐热老化性能和相容性的影响。结果表明,BR的加入改善了MVQ/ACM并用胶的力学性能和耐热老化性能,当白炭黑用量为30份、BR/MVQ/ACM的并用比为25/45/55时,并用胶的力学性能和耐热老化性能最好;最佳硫化工艺参数为70℃×10 MPa×30 min;加入BR可以改善MVQ/ACM并用胶的相容性,且使其玻璃化转变温度降低,耐低温性能提高。     

交联密度对HNBR/聚甲基丙烯酸正丁酯IPN阻尼性能的影响

用序列法制备氢化丁腈橡胶(HNBR)/聚甲基丙烯酸正丁酯(PnBMA)互穿聚合物网络(IPN)材料,通过改变两网络的硫化剂用量得到不同交联密度的HNBR/PnBMA IPN。采用动态粘弹谱仪测试IPN的阻尼性能,结果表明HNBR/PnBMA IPN材料的阻尼特性与交联密度密切相关。随着第一网络交联密度的增加,阻尼曲线逐渐由双峰转变为单峰,阻尼峰宽降低。第二网络交联密度的增加使阻尼曲线整体下降,双峰形态不变。通过改变两网络的交联密度可调整阻尼峰的位置、宽度及阻尼峰值。     

Sequential interpenetrating polymer networks of novolac resin and poly(2‐ethyl hexyl acrylate)—thermal,mechanical, and morphological study

Interpenetrating polymer networks (IPN) of novolac/poly (2‐ ethyl hexyl acrylate) (PEHA) have been prepared via in situ sequential technique of IPN formation. Full and semi‐IPNs were prepared with different blend ratios (w/w) e.g., 90 : 10, 80 : 20, and 70 : 30 in which the major constituent was novolac resin. A gradual decrease in specific gravity and hardness values was observed with increase in PEHA incorporation. A steady decrease in crosslink density with increase in PEHA fraction in the IPNs was quite evident. The IPNs were characterized with respect to their mechanical properties, e.g., ultimate tensile strength, percentage elongation at break, modulus, and toughness. Thermal behavior was studied by differential scanning calorimetry and thermogravimetric analysis. A plasticizing influence of PEHA on the rigid, brittle, and hard matrix of crosslinked phenolic resin is evidenced from the mechanical and thermal properties. The two‐phase surface morphology is revealed by scanning electron microscope. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and characterization of high performance,transparent interpenetrating polymer networks with polyurethane and poly(methyl methacrylate)

Transparent, interpenetrating polymer network (IPN) materials were synthesized using polyurethane (PU) and poly(methyl methacrylate) (PMMA). PMMA contributed to the transparency and rigidity necessary for use in impact‐resistant applications, whereas PU contributed to toughness. Several factors affecting the physical properties, such as the ratio of PU to PMMA, curing profile, inclusion of different isocyanates for the PU phase, and use of an inhibitor in the PMMA phase, were investigated. Full‐IPNs were synthesized so that the two polymer networks would remain entangled with one another, and domain sizes of each system were reduced, mitigating phase separation. Both simultaneous IPNs, polymerization of monomers occurring at the same time, and sequential IPNs, polymerization of monomers occurring at different temperatures, were synthesized for studying the reaction kinetics and final morphologies. The phase morphology and the final thermal and mechanical properties of the IPNs prepared were evaluated. Findings suggest that samples containing ～80 wt% PMMA, 1,6‐diisocyanatohexane 99+% (DCH), and an inhibitor with the MMA monomer created favorable results in the thermo‐mechanical and optical properties. POLYM. ENG. SCI. 2013. © 2012 Society of Plastics Engineers     

硅橡胶/丁苯橡胶并用胶的制备及表征

针对硅橡胶具有较高的耐热性,但力学性能差;丁苯橡胶(SBR)力学性能较好,但粘性较差;提出了将硅橡胶与SBR共混,制成共混材料;采用偏光显微镜、傅里叶变换红外光谱、差示扫描量热仪以及力学性能、热老化性能测试手段,研究了甲基乙烯基硅橡胶(MVQ)/SBR共混体系的并用比(质量比)、硫化工艺参数以及顺丁橡胶(BR)的加入对力学性能、耐热老化性能和相容性的影响。结果表明:MVQ与SBR最佳配比为30/70,白炭黑为45份;最佳硫化工艺参数为170℃×10 MPa×30 min。MVQ/SBR并用胶的玻璃化温度为-20℃,MVQ和SBR具有较好的相容性。