环氧化天然橡胶改性的丁苯橡胶/白炭黑复合材料的形态和性能

以环氧化天然橡胶为改性剂制备了丁苯橡胶/白炭黑复合材料,研究了环氧化天然橡胶对丁苯橡胶/白炭黑复合材料微观形态和力学、耐热、耐老化及动态力学性能的影响.结果表明,少量环氧化天然橡胶的加入改善了填料在橡胶基质中的分散,提高了丁苯橡胶/白炭黑复合材料硫化胶的定伸应力、拉伸强度、撕裂强度和耐磨性能,降低了其动态压缩疲劳生热速...     

改性石墨烯/天然橡胶复合材料的制备及性能

用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)对石墨烯(GE)进行改性,将得到的改性石墨烯(KHGE)与天然橡胶(NR)进行混炼制备出改性石墨烯/天然橡胶(KH-GE/NR)复合材料。采用傅里叶变换红外光谱仪、拉曼光谱仪、X射线衍射仪和扫描电镜对改性前后石墨烯的结构进行了表征,考察了KH-GE/NR复合材料的硫化性能、力学性能和导电性能。结果表明:KH-570对GE改性后,增大了GE的层间距,使GE在NR基体中的分散得到了改善;随着KH-GE用量的增加,KH-GE/NR复合材料力学性能提高,当KH-GE质量比(即KH-GE质量占NR质量的百分数,下同]为1.0%时,KH-GE/NR复合材料的拉伸强度和断裂伸长率分别为17.57 MPa和645.48%,比未添加KH-GE的复合材料分别提高了122%和21%,当KH-GE质量比为2.5%时,KH-GE/NR复合材料的体积电阻率最终下降约3个数量级。     

天然橡胶/白炭黑母炼胶、制备方法及天然橡胶/白炭黑复合材料

天然橡胶/白炭黑母炼胶、制备方法及天然橡胶/白炭黑复合材料     

天然虾青素防晒效果的研究

采用紫外分光光度法测定天然虾青素的吸光度,来研究天然虾青素是否具有防晒效果。通过对天然虾青素的吸光性、热稳定性和光稳定性等实验,实验结果表明天然虾青素具有良好的紫外吸收性,特别是吸收UVA有很好的效果,同时天然虾青素也具有良好的热稳定性和光稳定性;将天然虾青素复配为防晒霜后,防晒效果明显增强;其抗氧化性可以很好的修复晒后损伤的皮肤。虾青素是一种天然的防晒剂,在生产中可考虑取代部分化学防晒剂,从而使防晒产品更安全,效果更突出。     

天然虾青素的提取纯化及其应用

本文对从虾加工废弃物中提取虾青素(Astaxanthin)的常用方法进行了评述。碱提法对环境污染严重,虾青素易被氧化成为虾红素(Astacene);油溶法提取效率高,但提取物不易与高沸点的油分离;低沸点有机溶剂如二氯甲烷等是提取虾青素的有效溶剂,可借助蒸馏技术将溶剂循环利用;超临界萃取法可避免虾青素的降解,可得到高品质的产品,但生产成本高。同时,综述了虾青素在食品、保健品、医药和着色剂等领域中的应用。     

乳液共凝法制备天然橡胶/白炭黑复合材料的性能

以硅酸钠为前驱体,将一定浓度的硅酸钠溶液与天然胶乳共混共凝,使胶乳的凝聚与白炭黑的生成同步发生,从而制得天然橡胶/白炭黑复合材料,并与用传统混炼法制备的复合材料进行了性能对比。结果表明,当白炭黑用量为15份(质量)时,与混炼法相比,采用乳液共凝工艺所制备复合材料的力学性能明显更好,其中拉伸强度和撕裂强度分别提高了62.4%和87.7%;填料粒子在橡胶基质中的分散更为均匀,在60~80℃下的损耗因子也更低。     

改性白炭黑补强天然橡胶的性能研究

采用偶联剂Si69对白炭黑进行表面改性,研究改性白炭黑对天然橡胶胶料性能的影响。结果表明:与未改性白炭黑胶料相比,改性白炭黑胶料的加工安全性和硫化效率提升,硫化胶的300%定伸应力、拉伸强度、撕裂强度、耐磨性能和耐2级裂口屈挠性能提高,滚动阻力和动态生热性能略有改善,但抗湿滑性能略有下降;扫描电镜分析表明,改性白炭黑在橡胶基体中的分散性及其与橡胶基体的相容性改善。     

改性石墨烯/天然橡胶复合材料的制备及性能研究

本研究采用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)对石墨烯(GE)进行改采用γ-甲基丙烯酰氧基丙基三甲氧基硅烷（KH-570）对石墨烯（GE）进行改性,将得到的改性石墨烯（KH-GE）与天然橡胶（NR）进行混炼制备改性石墨烯/天然橡胶（KH-GE/NR）复合材料。采用傅里叶红外光谱仪、拉曼光谱仪、X射线衍射仪和场发射扫描电镜对改性前后石墨烯结构进行表征,同时研究了KH-GE/NR复合材料的硫化性能、力学性能和导电性能。结果表明：硅烷偶联剂KH-570对GE改性后,增大了GE的层间距,改善了GE在NR基体中的分散;随着KH-GE用量增加,KH-GE/NR复合材料力学性能提高,当KH-GE质量分数为1.0 %时,KH-GE/NR复合材料的拉伸强度和断裂伸长率分别为17.57Mpa和645.48%,比未添加KH-GE的复合材料分别提高122%和21%,同时复合材料的体积电阻率最终下降约三个数量级。     

虾青素制备新方法研究

用南极红酵母（Rhodotorula sp）NJ-0211发酵生产虾青素。考察了摇床的转速、培养时间和培养温度对南极红酵母培养的影响,确定了NJ-0211的最佳培养条件为转速100r／min,时间10d,温度4℃。在此培养条件下,虾青素的含量为873．75μg／g干菌体,比文献报道的高2．5倍。     

有机湿法改性白炭黑对天然橡胶复合材料性能的影响

分别采用双-[3-（三乙氧基硅）丙基]-四硫化物（偶联剂Si69）、离子液体1-丁基-3-甲基咪唑六氟磷酸盐（BMI）、离子液体1-烯丙基-3-甲基氯化咪唑（AMI）对白炭黑进行改性,制备改性白炭黑/天然橡胶（NR）复合材料。研究改性剂对改性白炭黑/NR复合材料的微观结构、硫化特性、物理性能和动态力学性能的影响。结果表明：改性白炭黑的粒径明显减小,其在橡胶基体中的分散性改善,与橡胶基体之间的相互作用增强;改性白炭黑/NR复合材料的硫化速率加快,物理性能明显提高;与偶联剂Si69相比,两种离子液体明显提高改性白炭黑/NR复合材料的硫化效率和物理性能;随着应变和频率的增大,白炭黑/NR复合材料的储能模量从大到小的填料顺序为AMI改性白炭黑、BMI改性白炭黑、偶联剂Si69改性白炭黑、未改性白炭黑;AMI改性白炭黑/NR复合材料的综合性能最好。     

The effects of natural astaxanthin-modified silica on properties of natural rubber

Natural astaxanthin is a natural substance extracted from algae such as Haematococcus pluvialis. Its molecular structure contains conjugated double bonds as well as keto and hydroxyl groups, and therefore it has high activity. In this research, natural astaxanthin was used to modify the surface of the silica, and its effects on natural rubber vulcanization properties, physical and mechanical properties, dynamic properties, and antiaging properties were studied by means of rubber process analyzer, dynamic mechanical anaylsis, and scanning electron microscopy. The results showed that natural astaxanthin-modified silica could reduce the degree of delayed vulcanization. At the same time, the resilience and abrasion resistance of the obtained vulcanizates were increased. The DIN abrasion volume of the vulcanizates modified and reinforced by the second strategy decreased by 19.2% and 23.6%, respectively; the Payne effect of the natural astaxanthin-modified silica/NR composites was weakened, and the dispersibility of the filler and the compatibility with the rubber matrix was significantly improved. Regardless of which strategy was used to modify the silica, the vulcanizates had a lower rolling resistance. Specially, it could greatly improve the hot air aging resistance property of rubber. Natural astaxanthin as being a renewable feedstock is expected to have a quite broad applications in the rubber industry. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 136, 47287.     

Preparation and performance of oleylamine modified silica-reinforced natural rubber composites

Oleylamine (OA) modified silica (SiO₂-g-OA) was prepared using γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560) and OA, silica/natural rubber (NR) and SiO₂-g-OA/NR composites were prepared by mechanical blending in an internal mixer, and SiO₂-g-OA was characterized by Fourier transform infrared spectroscopy, thermal gravimetric analyzer, and contact angle analyzer. The mechanical properties, abrasion resistance, curing characteristics, Payne effect, and morphology of silica/NR and SiO₂-g-OA /NR composites were investigated using universal testing machine, Akron abrasion tester, rubber processing analyzer, and scanning electron microscope, respectively. The results showed that SiO₂-g-OA became more hydrophobic and had better compatibility with NR. Moreover, SiO₂-g-OA/NR had weaker Payne effect, better vulcanization performance, and more excellent mechanical properties. As the content of filler was more than 30 phr, SiO₂-g-OA/NR had lower rolling resistance and higher wet skid resistance. Compared with silica modified by other coupling agents, SiO₂-g-OA had the best reinforcement effect on NR.     

白炭黑用量对氯丁橡胶/天然橡胶共混物性能的影响

研究了不同用量的沉淀法白炭黑填充质量比75/25的氯丁橡胶/天然橡胶共混物的物理机械性能、耐热老化性能和耐油性能,并用扫描电镜研究了共混物的结构。结果显示,白炭黑的加入改善了共混硫化物的拉伸强度、100%定伸应力和邵尔A硬度。压缩永久变形减小,黏度增大,从而导致在形变的过程中天然橡胶分散相占有率相对减少。相关性能也证明随着白炭黑用量的增加,硫化胶的耐热和耐油性能显著提高。     

Mechanical properties of natural rubber/grafted cellulose fibre composites

Mechanical properties of natural rubber/allyl acrylate and allyl methacrylate grafted cellulose fibre composites are presented. Stress/strain measurements and dynamic mechanical measurements indicate that the adhesion between grafted fibres and matrix is better than that in samples containing untreated cellulose fibres. This makes it possible to vary the composite properties by varying the fibre type and/or fibre amount.     

改性氨基硅溶胶/天然乳胶膜材料的制备、结构及性能

采用阳离子乳化剂聚二烯丙基二甲基氯化铵(PDDA)对氨基硅溶胶进行改性制备改性氨基硅溶胶(MSS),然后将其与天然乳胶(NRL)进行杂凝聚制得MSS/NRL膜材料,分析了MSS,MSS/NRL膜材料的结构、粒径、Zeta电位及形态,考察了MSS/NRL膜材料的力学性能及耐紫外老化性能。结果表明,MSS与NRL共混后粒径较NRL增大;氨基硅溶胶经PDDA改性后呈弱正电性,能在杂凝聚共混环境下与带负电荷的乳胶粒子形成多层次核-壳结构;随着MSS添加量的增加,MSS/NRL膜材料的拉伸强度呈先增后减的趋势,当MSS质量分数为0.35%时,膜材料的拉伸强度达到21.98 MPa的最大值,扯断伸长率达到750%;MSS/NRL薄膜的耐紫外老化性能在老化12 h以后较NRL薄膜提高10%以上。     

Dynamic mechanical properties and hysteresis loss of epoxidized natural rubber chemically bonded to the silica surface

High‐temperature (180°C) molding of epoxidized natural rubber (ENR) filled with precipitated silica leads to chemical bond formation between epoxy groups of ENR and silanol groups of silica. The extent of chemical bond formation is further enhanced in the presence of the silane coupling agent N‐3‐N‐(vinyl benzyl amino)ethyl‐γ‐amino‐propyl trimethoxy silane mono hydrogen chloride (trade name Z‐6032). The results of hysteresis loss measurements show that hysteresis loss increases with increase in coupling agent loading as a result of the higher modulus of the compounds compared to that of the ENR–silica mix. The dynamic mechanical property measurements show that the addition of coupling agent increases the glass‐transition temperature. Whereas strain‐dependent dynamic mechanical properties show that filler structure breakdown increases with increasing loading of coupling agent. Sulfur‐cured systems show higher filler structure breakdown compared to that of nonsulfur systems. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2171–2177, 2002     

Cure characteristics and mechanical properties of hydrogenated natural rubber/natural rubber blends

The cure characteristics and mechanical properties of blends consisting of hydrogenated natural rubber (HNR) and natural rubber (NR) blends were investigated. The HNR/NR blends at 50/50 wt ratio were vulcanized using various cure systems: peroxide vulcanization, conventional vulcanization with peroxide, and efficient vulcanization with peroxide. The HNR/NR vulcanizates cured by the combination of peroxide and sulfur donor (tetramethylthiuram disulfide, TMTD) in the efficient vulcanization with peroxide exhibited the best mechanical properties. It was also found that the hydrogenation level of HNR did not affect the tensile strength of the vulcanizates. The tensile strength of the blends decreased with increasing HNR content because of the higher incompatibility to cause the noncoherency behavior between NR and HNR. However, the HNR/NR vulcanizate at 50/50 wt ratio showed the maximum ultimate elongation corresponding to a co‐continuous morphology as attested to by scanning electron micrographs. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

白炭黑/顺丁橡胶/丁苯橡胶复合材料力学性能的影响因素

研究了影响白炭黑/顺丁橡胶/丁苯橡胶复合材料力学性能的因素。结果表明,白炭黑(ZQ601)适宜的改性配方和条件为:聚乙二醇6000、油酸及硅烷偶联剂Si-69的用量均为2%(以白炭黑质量计,下同),硬脂酸质量分数1%;温度100℃,时间10 min。制备白炭黑/顺丁橡胶/丁苯橡胶复合材料适宜的硫化配方和条件为:氧化锌3.0份(质量,下同),硬脂酸2.0份,促进剂DM 0.5份,促进剂D0.5份,促进剂CZ 1.0份,防老剂4010 NA 1.0份,切片石蜡1.0份,硫黄0.5份,改性白炭黑90份;温度140℃,时间10 min。所制备复合材料的拉伸强度、扯断伸长率、撕裂强度及邵尔A硬度分别达到了6.54 MPa、474%、20.11 kN/m和56,符合农业用轮胎及垫带的国标要求。     

聚苯胺改性蒙脱土/天然橡胶纳米复合材料的制备与性能

采用原位聚合法制备了聚苯胺质量分数为20% 的聚苯胺改性蒙脱土,并以此作为增强剂利用机械混炼法制备了聚苯胺改性蒙脱土( PANI － MMT) /天然橡胶( NR) 纳米复合材料。使用X 射线衍射仪、傅里叶变换红外光谱仪及扫描电镜等对PANI － MMT 和PANI － MMT/NR 复合材料的结构进行了表征,并考察了PANI － MMT/NR 复合材料的力学性能。结果表明,PANI － MMT/NR 复合材料形成了插层型纳米结构; 与普通的有机蒙脱土/NR 复合材料相比,PANI － MMT/NR 复合材料的力学性能明显提高,PANI － MMT 添加质量为20 份时其力学性能达到最好,并超过了添加40 份炭黑N 660 的NR 的力学性能。     

纳米氧化锌/二氧化硅杂化体的制备及其对天然橡胶复合材料性能的影响

采用3-氰基丙基三乙氧基硅烷（CTOS）对二氧化硅（SiO₂）进行了氰基化改性,并采用热溶剂法将纳米ZnO沉积于氰基官能化SiO₂（SiO₂-CN）表面,制备出纳米氧化锌/二氧化硅杂化体（ZnO@SiO₂）,并使用X射线衍射仪、傅里叶变换红外光谱仪、扫描电镜等对杂化结构进行表征。将ZnO@SiO₂作为填料添加入天然橡胶中制备复合材料（NR/ZnO@SiO₂）,然后对ZnO@SiO₂与橡胶的界面关系进行了分析,并研究了ZnO@SiO₂对橡胶复合材料的硫化特性、力学性能的影响。结果表明,纳米ZnO成功沉积在SiO₂-CN表面,并且NR/ZnO@SiO₂复合材料表现出优异的机械性能和硫化特性。与天然橡胶相比,仅添加5份杂化体的NR/ZnO@SiO₂复合材料的拉伸强度、100%定伸及300%定伸强度分别增加了150.2%、86.2%和65.5%,并且正硫化时间缩短了38.5%。