羧基丁苯胶乳水泥浆的制备及性能研究

羧基丁苯胶乳是一种稳定且含有表面活性剂水溶液的聚合物粒子分散体。作为水泥的添加剂,用于改进水泥砂浆或混凝土的性能,它既要求改性后的水泥材料抗压强度、抗张强度、耐水、耐候性能好,同时又要求胶乳的粘结力强,并与水泥易掺混,在常温下可快速成膜。因此在研究过程中不仅要考虑到胶乳乳液聚合过程,还要考虑到许多影响胶乳性能和最终用途的因素,从而使改性的水泥砂浆可适用于不同的领域。本文综合运用表面活性剂技术、外加剂复配技术以及水泥石物相微观分析测试技术,研究了羧基丁苯胶乳对不同体系的水泥石力学性能的影响。实验结果表明,在羧基丁苯胶乳适当加量下的,使油井水泥浆流变性、强度、稠化时间、和降失水性能都有很大的改善,有助于水泥环在后续施工过程中维持长期有效层间封隔。     

丁苯胶乳改性沥青的制备与性能

研究了不同用量的SBR胶乳对沥青的改性效果,考察了基质沥青改性后的性能.结果表明:采用SBR胶乳改性沥青,能改善基质沥青的高温性能、感温性能和抗热老化性能,特别可以更好的改善沥青的低温性能.     

丁苯胶乳复配乳化沥青防腐涂料制备及性能研究

为了有效控制建筑结构表层腐蚀问题,采用丁苯胶乳复配乳化沥青,同时添加复合型阻燃剂制备防腐涂料,并研究其抗酸碱盐腐蚀、抗剥落性能以及耐火阻燃性能。结果表明,选用7∶3的丁苯胶乳复配乳化沥青,固化剂用量16%,复合型阻燃剂用量5%,分散剂用量1%,成膜助剂用量3%,涂层厚度为100μm时,制备的防腐材料具有优良的耐水、耐盐、耐酸和耐碱性能,同时具备一定的耐火阻燃性能,但抗冻融循环性能较差。     

改性水泥专用丁苯胶乳的稳定性研究

以十二烷基苯磺酸钠为乳化剂,用过硫酸钾引发体系,制备了改性水泥专用丁苯胶乳,考察了乳化剂浓度、进料方式和搅拌形式对胶乳稳定性的影响.     

高分散性丁苯胶乳的制备及其对水泥的改性

添加传统丁苯胶乳进行改性,大大提高了水泥的力学性能,但是改性后的水泥材料流动性能差,抗压性能损失较多。为了提高添加丁苯胶乳后水泥的流动性及降低抗压性能损失,本文对丁苯胶乳进行改性,以苯乙烯与聚丁二烯作为核层、带有苯环的对苯乙烯磺酸钠作为壳层,制备出核壳型丁苯（SSBR）胶乳。把新合成的SSBR胶乳加入水泥后,对水泥力学性能进行表征,由于SSBR胶乳中与磺酸根相连的是苯环刚性链,空间位阻效应明显,添加8% SSBR胶乳水泥浆的流变指数增大为0.898,分子链强度大,水泥石的7天抗压强度损失量为2.31%,损失不明显,同时抗折强度提高17%。对SSBR胶乳改性水泥石材料力学性能的作用机理进行探究,结果表明,SSBR胶乳填充作用明显,吸附作用较强,增大水泥浆流动性能,且胶乳粒子可以与Ca²⁺络合,形成三维网状空间立体结构,从而达到增强水泥石力学性能强度,提高水泥石韧性的目的。     

水泥改性用丁苯胶乳的合成

采用种子乳液聚合法制备了丁苯共聚物/水泥复合材料专用丁苯胶乳,考察了复合乳化剂体系、种子胶乳用量、极性单体种类、聚合温度及加料方式等对乳胶粒尺寸及其分布和胶乳稳定性等的影响。结果表明,在小粒径种子体存在下,分批加乳化剂的加料方式是合成水泥专用丁苯胶乳的有效途径之一,平均粒径小且粒径分布窄的丁苯胶乳具有较好的稳定性。采用复合乳化剂体系、添加少量带极性的第三单体等可以较好地提高丁苯胶乳的化学和机械稳定性。     

羧基丁腈胶乳/羧基丁苯胶乳并用胶乳的性能研究

研究不同并用比羧基丁腈胶乳（XNBRL）/羧基丁苯胶乳（XSBRL）并用胶膜的性能以及考察并用胶乳的相容性。结果表明：XNBRL/XSBRL的并用比为90/10时,XNBRL/XSBRL并用胶膜的t90最短,并用硫化胶膜的交联密度较大、拉伸强度最大（33.8 MPa）以及溶胀指数最小（2.10）;XNBRL/XSBRL并用胶乳的粘度略大于XNBRL;随着XSBRL用量的增大,并用胶乳的机械稳定性变差,但变化幅度不大;XNBRL硫化胶膜和XNBRL/XSBRL并用硫化胶膜均仅有1个玻璃化温度,即XNBRL与XSBRL相容性很好,且XNBRL/XSBRL并用胶乳为均相体系;XNBRL/XSBRL并用硫化胶膜的XNBRL相与XSBRL相之间发生了化学键合,产生了共交联。     

丁苯胶乳改性乳化沥青常规性能及流变性能研究

为研究丁苯橡胶(SBR)胶乳掺量对于乳化沥青常规性能和流变性能的影响,通过储存稳定性和3大指标试验研究了SBR胶乳改性乳化沥青的常规性能,采用动态剪切流变试验(DSR)和弯曲梁流变试验(BBR)分析了SBR胶乳掺量对于乳化沥青高低温流变性能的影响。结果表明,SBR胶乳会降低乳化沥青的储存稳定性,可显著减小针入度和提高软化点、延度,增强乳化沥青的高温抗变形和低温延性;SBR胶乳可提高乳化沥青的车辙因子和减小相位角,改善乳化沥青抗车辙能力,并能降低蠕变劲度,增大蠕变速率和蠕变劲度与蠕变速率的比值,提高乳化沥青的低温抗裂性能。适宜的SBR胶乳掺量为4%。     

高固含量丁苯胶乳制备的研究进展

介绍了高固含量丁苯胶乳制备过程中存在的技术难题和该方面的理论、模型等,综述了提高丁苯胶乳固含量常用的方法,并结合现有的理论和实验基础对高固含量胶乳制备进行了展望。     

油井水泥专用丁苯胶乳的实验评价

针对传统丁苯胶乳在油井水泥浆中适用性能差的问题,采用种子乳液聚合方法合成了一种油井水泥专用丁苯胶乳,并对其进行了微观结构和应用性能评价。该丁苯胶乳物理性能、红外及热失重分析结果表明：该丁苯胶乳乳液稳定性好,高温下分子结构稳定。丁苯胶乳水泥浆的应用性能结果和微观结构分析表明：该丁苯胶乳水泥浆API失水可控制在50 mL内,耐盐性能好,可解决传统胶乳水泥浆稠化实验"鼓包"、"包心"等问题;加有该丁苯胶乳的水泥浆早期强度发展快,胶凝强度过渡时间短;丁苯胶乳能细化水泥浆的孔径结构,提高水泥浆的胶结强度和形变能力,并且其水泥石的柔韧性比原浆水泥石提高了30%;此外,能够满足深井、超深井和气井等复杂井的固井作业要求。     

Preparation and properties of silica/styrene butadiene rubber masterbatches by latex co‐coagulating technology

Silica/styrene butadiene rubber (SBR) masterbatches were prepared by co‐coagulating SBR latex and silica aqueous suspension. The X‐ray diffraction patterns and scanning electron microscopy were employed to characterize the microstructure of the composite. The content and utilization of silica of silica/SBR masterbatches were also investigated. The highest content of silica was achieved when amount of silica is 50 g. Then the cure characteristics, swelling ratio, thermal stability, and mechanical properties of vulcanizates prepared from the masterbatches were compared with those prepared by a conventional direct mixing method. The results revealed that higher maximum torque, shorter cure time, and better swelling resistance of silica/SBR masterbatches were obtained than conventional silica filled composites. The mechanical properties of silica/SBR masterbatches exhibited greater tensile strength and hardness compared to the corresponding conventional mixes. Additionally, the silica/SBR masterbatches vulcanizates exhibited better abrasion resistance, rolling resistance and heat build‐up to those of the conventional composite. POLYM. COMPOS., 35:1212–1219, 2014. © 2013 Society of Plastics Engineers     

丁苯吡胶乳的市场分析

丁苯吡胶乳(VPL)是由丁二烯、苯乙烯和2-乙烯基吡啶(2-VP)通过乳液聚合制成的三元水分散体,由于吡啶环上氮原子的极性,使得丁苯吡胶乳与合成纤维的粘合性显著优于天然胶乳和其他合成胶乳。丁苯吡胶乳广泛用于轮胎、胶带、胶管等骨架材料——纤维帘线、帘布和线绳等的浸胶胶粘剂,是橡胶纤维复合制品不可缺少的配套材料,其品质的优劣对浸胶骨架材料的粘合性能起关键作用。     

接枝改性淀粉/丁苯橡胶复合材料的制备与性能研究

采用固相法制备了玉米淀粉接枝马来酸酐(MAH)、甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)的共聚物Starch-g-MAH/MMA/BA(SMMB)。采用机械共混法制备了接枝改性淀粉/丁苯橡胶(SMMB/SBR)复合材料,研究了复合材料的力学性能、动态力学性能以及微观形态。结果表明,SMMB/SBR复合材料的力学性能优于未改性淀粉/SBR复合材料和纯SBR。与纯SBR硫化胶相比,SMMB/SBR复合材料的玻璃化转变温度(Tg)升高。微观形态分析显示,淀粉经改性后粒子尺寸减小,在SBR中的分散性得到了改善,与SBR基体的相容性得到了提高。     

Corrosion protection supplied by styrene butadiene latex modified zinc-rich primer

Using silica sol and potassium silicate as the raw materials and styrene butadiene emulsion as modifier, a stable high-modulus potassium silicate composite material was prepared with zinc powder at a ratio of 3:7 in the preparation of high modulus potassium silicate waterborne inorganic zinc-rich primer. Coatings were applied to steel panels with a composition of 8, 10, 12, and 15 wt % styrene butadiene latex. Scanning electron microscopy, energy-dispersive spectrometry, X-ray photoelectron spectroscopy, and electrochemical tests were utilized to analyze the anticorrosion properties of the samples. According to the results of electrochemical tests, the addition of styrene butadiene latex improves the corrosion resistance of coatings. The best corrosion performance can be obtained for the sample with 10 wt % styrene butadiene latex. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48918.     

Rheological properties of styrene butadiene styrene polymer modified road bitumens

The use of polymers for the modification of bitumen in road paving applications has been growing rapidly over the last decade as government authorities and paving contractors seek to improve road life in the face of increased traffic. Currently, the most commonly used polymer for bitumen modification is the elastomer styrene butadiene styrene (SBS) followed by other polymers such as styrene butadiene rubber, ethylene vinyl acetate and polyethylene. This paper describes the polymer modification of two penetration grade bitumens with SBS. Six polymer modified bitumens (PMBs) were produced by mixing the bitumens from two crude oil sources with a linear SBS copolymer at three polymer contents. The rheological characteristics of the SBS PMBs were analysed by means of conventional as well as dynamic mechanical analysis using a dynamic shear rheometer (DSR). The results of the investigation indicate that the degree of SBS modification is a function of bitumen source, bitumen-polymer compatibility and polymer concentration, with the higher polymer concentrations in a high aromatic content bitumen producing a highly elastic network which increases the viscosity, complex modulus and elastic response of the PMB, particularly at high service temperatures. However, ageing of the SBS PMBs tends to result in a reduction of the molecular size of the SBS copolymer with a decrease in the elastic response of the modified road bitumen.     

Cationic latex interaction with pulp fibers. II. Modification of sheet properties by styrene butadiene latex with quaternized amino groups

Unbeaten kraft fibers covered with experimental cationic latexes were formed into sheets in which direct fiber-fiber bonds are replaced by polymeric bonds. The effect on sheet properties—breaking length, elongation at break, folding endurance, opacity, and light scattering—was evaluated as a function of latex composition. The composition was altered by either the ratios of styrene to butadiene in the polymer or by mixing soft film-forming and hard nonfilming latex. It is shown that, regardless of latex composition and mechanical properties of the polymeric film, all the latexes can modify the sheet properties to a similar extent, providing that the sheets are heated above the polymer's glass transition temperature. An improvement of tensile strength is accompanied by increased elongation. As a probable mechanism of reinforcement, it is suggested that the polymer acts as a filler of the fiber's surface irregularities, thus providing a larger contact area between fibers and an improved stress transfer between them.     

改性碱式氯化镁晶须/丁苯橡胶复合材料制备与性能研究

以工业活性轻烧氧化镁粉和盐酸为原料,采用水溶液法制备了碱式氯化镁晶须,继而采用硅烷偶联剂对碱式氯化镁晶须进行改性,然后将其与丁苯橡胶混炼得到改性碱式氯化镁晶须/丁苯橡胶复合材料,研究了改性碱式氯化镁晶须对丁苯橡胶力学性能及热学性能的影响。结果表明：采用水溶液法制备得到的碱式氯化镁晶须结构为Mg₂（OH）₃Cl·4H₂O,呈微细纤维状,分布较均匀,长径比大于20;改性碱式氯化镁晶须的加入,可以改善丁苯橡胶的机械强度和阻燃性能。     

丁苯吡胶乳机械稳定性能改进研究

在丁苯吡胶乳基本聚合条件的基础上，作者以乳化剂用量及配比、初相比、补加水量、聚合体系pH为研究条件对胶乳的机械稳定性进行了改进。     

固相法改性淀粉／炭黑／丁苯橡胶复合材料的制备与性能研究

采用固相法制备了淀粉接枝马来酸酐（MAH）和丙烯酸丁酯（BA）的共聚物Starch-gMAH／BA（SMB）。采用机械共混法用15phr的改性淀粉（SMB）代替等量的炭黑（CB）,制备了改性淀粉／炭黑／丁苯橡胶复合材料（SMt3／CB／SBR）,研究了复合材料的力学性能、热氧老化性能、动态力学性能以及微观形态。结果表明,SMB／CB／SBR复合材料的力学性能优于未改性淀粉／CB／SBR复合材料,拉伸强度及扯断伸长率等性能优于SBR／CB复合材料;且SMB／CB／SBR复合材料具有更好的耐热氧老化性能;与SBR／CB复合材料相比,SMB／CB／SBR复合材料具有更低的滚动阻力;微观形态显示,淀粉经改性后粒子尺寸减小,在SBR基体中的分散性得到改善,与SBR基体的相容性得到提高。     

Structure and properties of oil extended styrene butadiene block copolymers

The relationships between mechanical properties and structure of rapidly spin cast styrene-butadiene-styrene (SBS) block copolymers diluted with two different types of mineral oil are discussed. Small angle X-ray scattering (SAXS) measurements indicate that both oils go mainly into the rubbery polybutadiene phase. While during rapid spin casting the paraffinic oil improves the phase separation of polystyrene (PS) and polybutadiene (PB), the opposite is true for the aromatic oil. The measurements also suggest that the oils cause a preferential swelling of the superstructure along the longitudinal direction of the cylindrical PS domains. From this, it can be concluded that a larger number of interconnecting PB chains is present in the cross direction than in the longitudinal one. With increasing oil content, a further decrease of interconnecting chains in the latter direction may be the reason for the decrease of the tensile modulus. Furthermore, above a critical value of dilution (33 wt percent for paraffinic oil, 50 wt percent for the aromatic one), more and more spherical domains are formed instead of the cylindrical ones. This morphological transition explains the step present in the double logarithmic plot of the large strain tensile modulus as a function of oil dilution.