液体橡胶/环氧树脂复合材料的冲蚀磨损性能

用端异氰酸酯基聚丁二烯液体橡胶与环氧树脂制得反应物（ETPB）。在ETPB中分别加入质量分数为5％和10％的纳米Al2O3，并选择适宜的固化剂固化，制得ETPB／Al2O3复合材料。测试了水介质中环氧树脂、ETPB、ETPB／Al2O3复合材料的冲蚀磨损性能。用扫描电子显微镜（SEM）对几种材料磨损表面进行了观察。结果表明，端异氰酸酯基聚丁二烯液体橡胶改性环氧树脂可显著提高抗磨损性能，与通过填充纳米Al2O3无机粒子ETPB复合材料相比，其抗冲蚀性能更好。     

丁腈橡胶、腰果油改性酚醛树脂的研究

以丁腈橡胶粉和腰果油改性酚醛树脂为改性剂，通过对多种原料、橡胶助剂、摩擦性能调节剂的研究和配方筛选，制得高性能载重汽车刹车片内衬材料。该材料磨耗低、抗冲击强度高、硬度和摩擦系数适中、高温抗热衰退明显，生产过程中可省去投资大、能耗高的密炼工艺，具有重要的工业价值。     

羧基液体丁腈橡胶增韧改性环氧树脂研究

用羧基液体丁腈橡胶（CTBN）对环氧树脂（EP）进行改性,合成CTBN/EP预聚物。通过研究不同配比CTBN/EP体系的性能,确定CTBN对EP的增韧效果。     

Studies on the Tensile Properties of Rubberwood Fibre-Natural Rubber Composites

Abstract

Natural rubber (NR) composites were prepared by incorporating rubberwood fibres at different loadings into the NR matrix in a mixing mill according to a base formulation. Tensile properties, swelling measurement and tensile fracture surfaces of gum and composites with 0, 10, 20, 30 and 50 phr of rubberwood fibres were studied. Incorporation of rubberwood fibres in the composites increases the tensile modulus but reduces the tensile strength and elongation at break. Scanning electron microscopy (SEM) studies and swelling measurement indicate that the increasing rubberwood loading has weakened the rubber-filler interactions.     

Preparation and Properties of Natural Rubber/Palygorskite Composites by Co-Coagulating Rubber Latex and Clay Aqueous Suspension

Natural rubber (NR)/Palygorskite composites were prepared by co-coagulating rubber latex and clay aqueous suspension. Org-palygorskite was attained by using cetyltrimethylammonium bromide (CTAB) and the four factors influencing the average diameter of palygorskite were discussed. Four optimal conditions of preparing minimum average diameter were determined which included the concentration of palygorskite, the concentration of sodium polyacrylate, ultrasonic time and ultrasonic power. Mechanical properties suggested that composites using modified palygorskite which were dispersed by ultrasonic wave were the best, the tensile strength, tear strength, 300% modulus and shall hardness increased by 77.14%, 118.18%, 242.86% and 65.2%, respectively. Modified palygorskite was shown by FTIR spectrogram and observed by ESEM. Modified palygorskite dispersed by ultrasonic wave were dispersed into the rubble uniformly, some stick particles inserted into the rubber and it is difficult to find stick shape, and there were 20% particles belonging to nanomaterials and 80% micromaterials.     

Mechanical and Anticorrosive Properties of Graphene/Epoxy Resin Composites Coating Prepared by in-Situ Method

The graphene nanosheets-based epoxy resin coating (0, 0.1, 0.4 and 0.7 wt %) was prepared by a situ-synthesis method. The effect of polyvinylpyrrolidone/reduced graphene oxide (PVP-rGO) on mechanical and thermal properties of epoxy resin coating was investigated using nanoindentation technique and thermogravimetric analysis, respectively. A significant enhancement (ca. 213% and 73 °C) in the Young modulus and thermal stability of epoxy resin coating was obtained at a loading of 0.7 wt %, respectively. Furthermore, the erosion resistance of graphene nanosheets-based epoxy resin coating was investigated by electrochemical measurement. The results showed also that the Rrcco (ca. 0.3 mm/year) of graphene nanosheets-based epoxy resin coating was far lower than neat epoxy resin (1.3 mm/year). Thus, this approach provides a novel route for improving erosion resistance and mechanical-thermal stability of polymers coating, which is expected to be used in mechanical-thermal-corrosion coupling environments.     

液态聚硫橡胶改性苯并噁嗪树脂的研究

为了提高苯并嗯嗪树脂的性能,使用液态聚硫橡胶对苯并嗯嗪树脂进行了改性研究。实验将不同配比的聚硫橡胶与苯并嚼嗪树脂进行共混并固化,利用傅立叶红外光谱（FTIR）、差示扫描量热法（DSC）、动态热机械分析仪（DMTA）分析了共混体系的结构、固化行为和玻璃化转变,测定了共混体系的热失重和冲击强度,分析比较了不同聚硫橡胶含量共混体系的结构、热性能和力学性能。结果表明改性苯并嗯嗪树脂的热性能和力学性能均得到不同程度的改善。得出如下结论：使用液态聚硫橡胶改性苯并嗯嗪树脂时,当聚硫橡胶加入量为5份（苯并嗯嗪树脂为100质量份）时,得到的改性树脂和纯嗯嗪树脂相比,韧性和热稳定性有显著提高,玻璃化转变温度也略有提高,复合材料的综合性能最好。     

Dynamic Mechanical Properties of EPDM Rubber Blends

The damping properties of ethylene-propylene-diene rubber (EPDM) with aliphatic hydrocarbon (C94) resin were investigated by dynamic mechanical analysis (DMA). It was found that the damping property of EPDM was improved after addition of aliphatic hydrocarbon resin. With increasing content of the resin, the main tan δ peak shifted to higher temperatures and the valid damping range in temperature was broadened. An addition of mica or NBR was found to widen the effective damping range. After addition of NBR into EPDM, the effective damping range of the blends was evidently extended in the applicable temperature region, especially when NBR content was 50 wt%. It was concluded that the NBR was incompatible with EPDM, and there existed two tan δ peaks in DMA spectra.     

集成橡胶结构组成对其白炭黑增强复合材料性能的影响

研究集成橡胶(SIBR)的结构组成对其白炭黑增强复合材料各项性能的影响,结果表明：SIBR中1,4结构(1,4-PB、1,4-PI),非1,4结构(St、1,2-PB、3,4-PI)的含量会影响其Tg、tanδ和硫化速率,进而影响白炭黑增强SIBR复合材料的滚动阻力、抗湿滑性、填料分散程度和拉伸撕裂性能等。SIBR的结构组成与其复合材料的物理机械性能和动态力学性能紧密相关。     

聚硫橡胶增韧环氧树脂模具材料的研究

以液态聚硫橡胶为增韧剂,低分子量聚酰胺为固化剂,制备聚硫橡胶/环氧树脂快速模具材料。以冲击强度、压缩强度和固化时间为考核指标,通过正交设计优化了固化温度、聚硫橡胶的加入量、固化剂的加入量和石墨用量等参数。结果表明:固化温度、固化剂用量对环氧固化物的冲击强度、压缩强度和固化时间的影响十分显著,液态聚硫橡胶明显改善了环氧树脂快速模具材料的力学性能,而石墨对其影响较小。综合冲击性能、压缩性能和固化时间三项指标,确定了环氧树脂模具材料的最佳制备条件为:固化温度70℃,聚硫橡胶加入量25%,固化剂加入量100%,石墨加入量30%。     

接枝改性法制备天然橡胶吸油材料的工艺研究

以丙烯酸丁酯为单体,N,N′-亚甲基双丙烯酰胺为交联剂,过氧化苯甲酰为引发剂,采用乳液聚合法合成吸油性橡胶。研究了引发剂和交联剂种类和用量、反应时间和温度、天然胶乳和单体配比对吸油性能的影响,并对吸油橡胶的吸油倍率及对水面浮油的回收性能等进行了考察。通过对煤油等几类油品的吸收对比,确定最佳的工艺条件。制得的吸油橡胶吸煤油最高可以达11.92g/g;吸四氯化碳为15.21g/g。     

Synthesis,Characterization and Glass Reinforced Composites of Acetone-Formaldehyde - Resorcinol Resins

Abstract

Acetone-Formaldehyde (AF) resin having methylol groups ([sbnd]CH₂OH) has been prepared and condensed with resorcinol (R) in the presence; of alcoholic alkali catalyst at varying ratios of AF:R; 1:1, 1:1.5 and 1:2. The resultant AF-R resins were characterized by elemental analysis, IR spectral studies, number average molecular weight (Mn) estimated by non-aqueous conductometric titration and thermogravimetry. The curing study of AF-R resins with Hexamethylenetetramine (HMTA) was monitored by Differential Scanning Calorimetry (DSC) and kinetic parameters were evaluated. The glass reinforced composites based on AF-R-HMTA system have also been prepared and characterized.     

端羧基液体丁腈橡胶增韧环氧树脂研究

制备了由端羧基液体丁腈橡胶（cTBN）增韧环氧树脂（ER）于室温下固化的双组分胶黏剂。研究了CTBN与ER配比、甲组分处理温度及其保温时间对胶黏剂剪切强度的影响并用扫描电子显微镜（SEM）观察了其微观形态。实验结果表明CTBN：ER=8：1、甲组分于200℃下反应2．5h时,胶黏剂剪切强度可以达到25．34MPa,耐介质性能良好。同时SEM测试结果表明端羧基液体丁腈橡胶对ER增韧作用明显,为提高环氧树脂的粘接性和韧性提供了技术依据。     

用改性环氧胶黏剂粘接硫化丁腈橡胶

以端异氰酸基聚氨酯预聚体改性环氧树脂和双氰胺为主要原料制备了一种单组分耐热环氧树脂胶黏剂,该胶可以对表面未处理的丁腈橡胶进行粘接。文中考察了增韧剂种类、增韧剂用量对粘接强度的影响,同时考察了促进剂种类和用量对凝胶时间和贮存期的影响。实验结果表明,该胶黏剂对丁腈橡胶的粘接强度好,具有较好耐热性和较长贮存期。     

NMMO法制备的球形纤维素珠体的性能研究

对N-甲基吗啉-N-氧化物(NMMO)制备的球形纤维素的物化性能进行研究,检测了球形纤维素珠体的含水率、粒径分布、耐酸碱能力,结晶结构,比表面积。结果表明,该法制备的球形纤维素珠体的含水率为74.0%,粒径主要分布在0.20～0.45mm,球形度好、比表面积大(190.5m2/g),耐酸碱度高。此外,利用NMMO法制备的球形纤维素珠体主要为纤维素(Ⅱ)结晶变体。     

Resorcinol in high solid phenol−formaldehyde resins for foams production

The acid curing agent content and foaming temperature could be reduced by improving the resol reactivity. In this study, highly active and solid phenol?resorcinol?formaldehyde copolymer resins (PRFRs) with different resorcinol/phenol (R /P ) molar ratios and formaldehyde/(phenol + resorcinol) [F /(P + R )] molar ratios were synthesized through the copolymerization of resorcinol, formaldehyde, and phenol. Phenol?resorcinol?formaldehyde foams (PRFFs) were prepared with synthetic PRFRs. The results showed that PRFR‐2 exhibited higher reactivity, faster curing speed, and better thermal stability. In addition, the foam produced with the PRFR‐2 had improved mechanical and flame retardation properties and a compressive strength of 0.18 MPa, a flexural strength of 0.25 MPa, and a limited oxygen index (LOI) greater than 37%. The increased reactivity of the PRFRs correlated with the changing mechanical properties of PRFFs because of the effects of resorcinol and the molar ratio of formaldehyde to phenol and resorcinol. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44881.     

Synergism Effect of Montmorillonite and Cellulose Whiskers on the Mechanical and Barrier Properties of Natural Rubber Composites

A series of nanocomposite films based on natural rubber (NR), Na⁺‐montmorillonite (MMT), and cellulose whiskers (W) was prepared, keeping a total filler content equal to 5 wt.‐%. In the binary NR/MMT system, small stacks of intercalated montmorillonites were homogeneously dispersed within the polymer matrix whereas they were clearly lying in the vicinity of cellulose whiskers in the ternary NR/MMT/W blends. The effects of MMT and W on mechanical and gas barrier properties of the nanocomposite films were investigated. A significant increase of the rubbery modulus was obtained upon filler addition. The reinforcing effect was particularly important for the nanocomposite film reinforced with 1 wt.‐% MMT and 4 wt.‐% W. The improvement of the gas barrier properties observed upon filler addition was explained by a tortuosity effect. The calculated tortuosity values indicated that the simultaneous use of MMT and W could greatly slow down the gas diffusion rate in NR. Formation of MMT‐W subassembly should be responsible for this synergism effect.

     

废橡胶粉改性及其在橡塑复合材料中的应用进展

对废旧胶粉的改性方法及原理作了简要介绍,重点综述了废橡胶粉在聚乙烯,聚丙烯,聚氯乙烯等橡塑复合材料中的研究和应用进展。对废橡胶粉在橡塑复合材料中的研究、开发和应用前景进行了展望。     

丁腈橡胶增韧改性环氧树脂的研究

通过羧基丁腈橡胶(XNBR)对双酚A环氧树脂(CYD-128)进行改性研究,制备了具有优良增韧效果的嵌段高分子预聚物。对制备过程的反应机理、合成条件、产品转化率等进行了比较深入的研究和探讨。结果表明:羧基丁腈橡胶与环氧树脂反应温度100～120℃、反应时间1.5～3h、催化剂用量0.20%～0.30%时,为最佳合成工艺;XNBR含量为15phr时,改性材料具有最大的断裂伸长率。     

Flame-Retardant,Thermal, Mechanical and Dielectric Properties of Structural Non-Halogenated Epoxy Resin Composites

First, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and epoxy resin (E-51) were employed to synthesize a structural non-halogenated epoxy resin (ED). And a novelphenolic aldehyde curing agent, 2,4,6-tri (phenol-methylene-amide)-triazine (MFP) was also synthesized for preparing high-performance MFP/ED composites. Results showed that, the flame-retardant and thermal stabilities of the composites were improved with the increasing phosphorus content. When the content of phosphorus was 3wt%, the initial decomposing temperature of the composite was over 325°C, and the charring rate was 30.3% at 650°C, could meet the requirements of UL 94-V0 rating. However, all the flexural and impact, dielectric constant and loss and the glass transition temperature (Tg) of the composites were decreased with the increasing phosphorus content.