高分散性沉淀法白炭黑的分散性测试与研究

采用激光衍射法测试高分散性沉淀法白炭黑的粒径分布以表征其分散性,并采用ISO 5794-3：2011《橡胶配合剂 沉淀水合二氧化硅 在溶聚丁苯橡胶（SSBR）和丁二烯橡胶（BR）混合物中的鉴定》中的基础配方和混炼工艺进行白炭黑应用性能试验,考察高分散性白炭黑的激光粒径分布与白炭黑在胶料中的分散性的关系。结果表明：采用激光粒径分布表征的白炭黑分散性与白炭黑在胶料中的分散性存在较强的相关性,在相同的比表面积下,白炭黑的D50（颗粒的中位径）和R18（直径大于18 μm的颗粒占比）越小,白炭黑在胶料中的分散性越好,胶料加工性能改善;使用该技术有助于改善高分散性白炭黑胶料的加工性能,大幅降低胶料加工成本,具有良好的经济效益和社会效益。     

高分散性白炭黑的分散性测试与研究

采用激光衍射法测试高分散性白炭黑的粒径分布,并根据ISO 5794-3:2011进行高分散性白炭黑应用性能试验,考察高分散性白炭黑粒径分布与其在胶料中分散性的关系。结果表明:采用激光衍射法测得的高分散性白炭黑粒径分布与高分散性白炭黑在胶料中分散性存在较强的相关性,高分散性白炭黑的D50(颗粒的中位粒径)和R18(直径大于18μm的颗粒占比)越小,高分散性白炭黑在胶料中的分散性越好。     

白炭黑分散性的有效评价研究

对4种白炭黑及其胶料性能进行分析,确定可评价白炭黑在胶料中分散性的性能项目。结果表明:用白炭黑的常规理化性能及硫化胶的基本物理性能不能有效评价白炭黑的分散性,依据白炭黑激光粒径分布、混炼胶Payne效应、混炼胶门尼粘度及硫化胶耐屈挠性能可有效评价白炭黑的分散性。     

轮胎用高分散性白炭黑

为了满足性能要求越来越高的轮胎市场对改进型补强填料的需求,罗地亚公司与一大轮胎公司的紧密使用,在20世纪80年代末发明了新一代的白炭黑,现在这种白炭黑的品种正不断增多。     

使用抗聚集能力表征白炭黑的分散性

首先证明白炭黑聚集是决定胶料模量的最主要因素,并且不受硫化网络的影响,然后尝试用白炭黑聚集程度之差[δ(ΔG′)(G′为弹性模量)]来表征白炭黑的分散性。研究结果表明:δ(ΔG′)越大,白炭黑的抗聚集能力越弱;δ(ΔG′)与胶料的门尼焦烧时间、定伸应力和拉伸强度都有非常好的相关性,进一步表明了δ(ΔG′)的研究意义。     

胶料组分对填料分散性的影响

研究胶料中组分对填料分散性的影响。结果表明:普通白炭黑胶料加入配合剂或硅烷偶联剂后有利于填料的分散;高分散性白炭黑的分散性优于普通白炭黑;硅烷偶联剂对无配合剂胶料中的填料分散起促进作用,且对普通白炭黑的促进作用高于高分散性白炭黑;高分散性白炭黑比表面积较大的分散性较差;氧化锌和硬脂酸对胶料中的填料分散起促进作用;炭黑分散性优于白炭黑。     

氯丁橡胶对炭黑/白炭黑填充溶聚丁苯橡胶性能的影响

研究了氯丁橡胶（CR）对白炭黑/炭黑并用填充溶聚丁苯橡胶（SSBR）的性能和填料分散的影响。结果表明,加入CR可提高炭黑/白炭黑填充SSBR的性能,当CR用量为4份时,硫化胶综合力学性能最佳;TEM观察表明,填料与SSBR基体界面模糊,填料分散较均匀,填料网络化程度降低。     

非轮胎类配方中的高分散性白炭黑

图1（略）举例说明了生产标准或传统白炭黑的典型生产过程。初始原料是硅酸钠溶液（通常称之为水玻璃）和硫酸。在可控条件下,将酸加到容器内的硅酸盐溶液中而生成白炭黑粒子和聚集体的沉析物。硫酸钠盐为沉淀反应的副产物。然后过滤生成物流并且将剩余的盐在压滤机中排掉。最后形成的滤饼经干燥（一般在滚筒干燥器内干燥)、碾磨成细粉后用气力输送到贮罐内。白炭黑粉末可包装在袋或装在散装容器内以便出售或再在造粒机中进行加工处理,得到低尘、高松密度的白炭黑。     

Synthesis, Characterization and Catalytic Properties of Chiral BINOL Functionalized Mesoporous Silicas for Enantioselective Morita-Baylis-Hillman Reaction

Several Chiral BINOL functionalized mesoporous silicas were prepared by post grafting of organosilane derivatives of (S)-BINOL (1,1′-bi-2-naphthol) on SBA-15 and characterized by ¹³C CP/MAS NMR, FT-IR, UV–visible absorption spectra, elemental analysis, powder XRD, nitrogen adsorption–desorption isotherms and TEM techniques. Their catalytic properties were demonstrated in enantioselective Morita-Baylis-Hillman reaction of 3-phenylpropanal and cyclohexenone. Among them, 3BSBA-15 linked through the 3 position of BINOL exhibit higher enantioselectivity (26% e.e.) and yield (88%) which are similar to the homogeneous catalyst (S)-BINOL (27% e.e. and 92% yield) as Brønsted acids catalyst, while complex of 3BSBA-15 and calcium 3BSBA-15-Ca show lower enantioselectivity (21% e.e.) than its homogeneous complex (S)-BINOL-Ca (32% e.e.) as ligand catalyst. 3BSBA-15 and 3BSBA-15-Ca can be reused with no significant decrease in enantioselectivity and yield.     

Rubbers Based on Conjugated Soybean Oil: Synthesis and Characterization

A range of bio‐based rubbery thermosets have been synthesized by the cationic copolymerization of conjugated soybean oil, styrene, and 1,5‐hexadiene or isoprene as flexible crosslinkers. The thermal, and mechanical properties, as well as the wear behavior, of these new bio‐rubbers are reported. The amount of styrene and the type of diene incorporated have the greatest influence on the properties of the final materials. The largest variations are found in glass transition temperature, storage modulus, tan δ values, crosslink density, and abrasive wear depth, while thermal degradation and extraction analyses showed minimal variations with changes in composition.

     

二氧化硅负载梳状聚醚三相催化剂的合成及其催化性能研究

以表面经偶联剂修饰的二氧化硅为载体,通过聚(β-氯乙基缩水甘油醚)和醇钠反应,合成了两种梳状聚醚三相转移催化剂,研究了它们在碘代、二氯卡宾对双键加成和混合醚制备反应中的催化活性.结果表明,这类催化剂具有良好的催化活性和重复使用性能.     

Characterization of MAO‐Modified Silicas for Ethylene Polymerization

A series of methylaluminoxane (MAO)‐modified PQ and EP 12 silicas, calcined at 110, 250, and 450°C, were prepared. The resulting MAO‐modified supports were characterized by a set of complementary techniques: Fourier transform infrared spectroscopy (FT‐IR), scanning electron microscopy‐energy dispersive X‐ray spectroscopy (SEM‐EDX), small angle X‐ray scattering (SAXS), and thermal gravimetric analysis (TGA). The Al/Si ratios of the MAO‐modified PQ and EP12 silicas were in the ranges of 0.19–0.27 wt % and 0.17–0.30 wt %, respectively. MAO‐modified silicas were used in the polymerization of ethylene using an Et₂IndZrCl₂ catalyst. The MAO‐modified PQ silica showed higher activity in comparison to the MAO‐modified EP12. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4568–4575, 2013     

Adhesion Properties of Rubbers Modified by Surface Active Substances

The introduction of anionic surface active substances into butadiene-styrene rubbers doubles or trebles the work of delamination (A) for fabric-rubber bonds. The increase of A is due to a rise in mechanical loss through a higher rate of relaxation of a polymer adsorbed by a filler (τ_H). A linear dependence between A and logτ_H is found.     

氯化橡胶和相关替代品在涂料行业中的应用评估

介绍了氯化橡胶的发展状况以及取代四氯化碳法生产氯化橡胶的必要性,主要对不同生产厂家的水相法氯化橡胶、溶剂法氯化橡胶、高氯化聚乙烯和氯醚树脂的各项性能进行了评估。     

Adhesion Properties of Rubbers Modified by Surface Active Substances

The introduction of anionic surface active substances into butadiene-styrene rubbers doubles or trebles the work of delamination (A) for fabric-rubber bonds. The increase of A is due to a rise in mechanical loss through a higher rate of relaxation of a polymer adsorbed by a filler (τ_H). A linear dependence between A and logτ_H is found.