14m^3氯乙烯搪瓷聚合釜传热性能的研究及分析

本文介绍了在生产装置上测定总传热系数K_实值的方法及实测K_实值,并且和理论计算出的K_理值作了比较,二者相当吻合。为了探讨提高K值的途径,进一步分析了影响K值的诸因素,提出了改善该类型聚合釜传热性能的建议。     

SG8型PVC在13.5m^3釜生产

合理的配方和工艺条件，控制链转移剂疏基乙醇的用量和加入程序，采用微机控制聚合温度，在国产１３．５ｍ＾３聚合釜生产出符合国标的ＳＧ－８型ＰＶＣ树脂。     

国产HPMC在13.5m^3釜的生产应用

国产ＨＰＭＣ在１３．５ｍ￣３釜的生产应用杭州电化股份有限公司孔万力ＨＰＭＣ作为ＰＶＣ生产过程中的一种主要分散剂之一，我公司为保证ＰＶＣ产品质量，一直选用日本信越产６０ＳＨ５０和美国道化学公司Ｅ－５０两种牌号。以前也曾尝试用国产ＨＰＭＣ，但因其质量稳定...     

高含固率污泥厌氧消化系统的启动方案与试验

高含固污泥厌氧消化技术是目前国内外的研究热点。该文以上海市白龙港污水处理厂脱水污泥稀释而成的含固率为10%的污泥作为研究对象,对高含固污泥厌氧消化技术进行了初步的探讨。试验结果表明,厌氧消化系统的进泥含固率升高至10%后,每投入1 m3的污泥产气约16~18 m3沼气,远高于现有浓缩污泥厌氧消化系统的产气率(8~10 m3沼气/m3污泥)。高含固率污泥厌氧消化系统推荐采用清水启动策略,即消化罐内介质的初始状态为清水(二沉池出水),之后以不同投配率投加原污泥,避免系统启动过程中的VFA的积累,尤其是丙酸含量的积累。该研究成果不仅可为该污水处理厂现有污泥厌氧消化系统未来的扩建改造服务,而且可为国内同类工程提供借鉴和示范。     

国产HPMC在30m^3聚合釜的生产试用

国产ＨＰＭＣ在３０ｍ￣３聚合釜的生产试用天津化工厂孟昭文，苏达江我厂生产悬浮法ＰＶＣ所用的分散剂羟两基甲基纤维素（ＨＰＭＣ）一直从国外进口。多年来国内ＨＰＭＣ生产厂家一直努力生产出合格的产品取代国外进口二，但由于质量较差，且不稳定，国内主要ＰＶＣ生产...     

提高127m^3聚合釜生产强度和产品质量措施

前言我厂聚氯乙烯车间有8台127m3聚合釜,是从日本引进的,原设计能力为20万办,后因公司扩建到28万t／a的要求,我厂在不增加釜数的基础上,通过技术改造,目前已基本实现扩建生产要求。同时通过聚合配方的改进,不仅使树脂质量有大幅度提高,而且开发出医用级树脂,增加了聚氯乙烯树脂的牌号和档次,取得了可喜成果。1提高生产能力1．1采用全自动化密闭操作和釜外回收单体技术127m3聚合釜操作一抽真空、试压、加料、聚合升温、聚合、单体回收、放料及清洗喷涂,原先全部在聚合釜内部进行,现改为带压出料技术,将反应后单体回收放在聚合釜…     

用45m^3聚合釜生产食品卫生级悬浮PVC树脂

介绍使用45m3聚合釜生产悬浮法PVC树脂技术,该树脂中氯乙烯残留量远远低于5×10-6、二氯乙烯含量低于1.5×10-4,达到了食品卫生级的要求.年销售利润增加720万元.基本配方为(质量份数):VCM 100,水170,分散剂(PVA+HPMC)0.04～0.08,引发剂(EHP)0.06～0.09,其它助剂0.18.     

HPMC—60RT50在13.5m^3聚合釜VCM悬浮聚合生产中的应用

采用国产羟丙基甲基纤维素（ＨＰＭＣ）６０ＲＴ５０做为主分散剂比采用５０９生产的聚氯乙烯树脂表观密度和吸油率都有提高。在显微镜下观察树脂颗粒形态非常规整，晶点和条状物明显减少，且树脂中ＶＣＭ残留量完全达到国标要求，故用６０ＲＴ５０完全可取代进口同类产品。     

127m^3PVC聚合釜搅拌试验研究

通过在与127m^3PVC聚合釜几何相似试验装置中的搅拌冷模试验,分析了不同搅拌器形式、挡板数量下的搅拌功率、流动形态和流场特性,为改进127m^3PVC聚合釜结构、提高生产能力提供参考。     

Composite latex production with high solid content

Poly(methyl methacrylate-co-butyl acrylate) (PMMA-co-PBA) and poly(sytrene-co-butyl acrylate) (PSt-co-PBA) latexes in which solid content (SC) varied from 20% up to 40 wt % armored with laponite clay have been successfully synthesized using a simple method, which does not require modification of the clay particles prior to polymerization. Incorporation of quite high amounts of laponite nanoparticles into PMMA-co-PBA and PSt-co-PBA latexes with a certain amount of solids content was achieved. The nanocomposite latexes and polymer samples were characterized using Fourier transform infrared (FTIR) spectroscopy in attenuated total reflectance (ATR) mode, dynamic light scattering (DLS), X-ray diffraction (XRD), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), contact angle, zeta potential, viscosimetry and analytical ultracentrifuge (AUC). Zeta potential values showed that stable latex was obtained and precipitation problem of the nanoparticles in the latex was not seen during the storage. Obtained nanocomposite latex showed fine particle size between 88 and 160 nm. TEM images and XRD results pointed out that the exfoliated nanocomposite structure for latexes was obtained. DSC analyzes showed that the glass-transition temperature (T _g) values of nanocomposite films decreased slightly compared with those of pure (PMMA-co-PBA) films. Mechanical properties of laponite clay armored PMMA-co-PBA were tested and compared with those of pure PMMA-co-PBA, indicating that incorporated the Young's modulus and tensile strength are also improved to a noticeable extent after the incorporation of laponite. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47423.     

高固含量阳离子聚丙烯酸酯乳液的制备

采用种子预乳化半连续法制得具有高固含量的阳离子型聚丙烯酸酯乳液,其乳液固含量达到41%。研究了引发剂、反应性乳化剂、乳液的软硬单体配比与聚合温度对乳液聚合稳定性和乳液性能的影响。结果表明:在乳液聚合体系中,引发剂用量为0.5%,反应性乳化剂用量为0.5%,软硬单体配比(MMA/BA)为2.0:1,聚合温度为80℃时,制备的乳液具有良好的稳定性、最佳性能以及对木材良好的封油效果。     

高固含量改性聚醋酸乙烯酯乳液的制备

通过半种子连续乳液聚合工艺,以过硫酸铵为引发剂,以非离子和阴离子乳化剂为复合乳化剂,加入一定量的保护胶体,利用叔碳酸乙烯酯（Veova10）和丙烯酸异辛酯（2-EHA）为改性单体,合成了高固含量的改性聚醋酸乙烯酯乳液。研究了乳化剂用量,阴／非离子乳化剂质量比,叔碳酸乙烯酯、丙烯酸异辛酯和保护胶体用量对合成乳液的稳定性、黏度及吸水性的影响。研究结果表明,乳化剂质量分数为3．0％,阴／非离子乳化剂质量比为1：2,叔碳酸乙烯酯质量分数为20％,丙烯酸异辛酯质量分数为10％,保护胶体质量分数为0．25％时,乳液具有较好的稳定性、耐水性和成膜性。     

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。     

丁苯道路胶乳工业试生产

用减粘剂法釜式（卧式蒸发器）外循环加热真察觉有缩工艺生产了固体物质量分数为４５％的道路胶乳,工业试生产表明,适宜的操作条件为：温度７０～７５℃,真空度－０．０８５ＭＰａ,脱水量３８０～５００Ｌ／ｈ,胡阒浓缩过程中碱性助剂的加入,产品胶乳的ｐＨ值比原料胶乳的高出０．４～２．０,减粘剂的加入速度过快会使胶乳产生絮凝,造成设备堵挂,而且使产品色相呈灰白色,碱性助剂的加料时间以不少于１ｈ为宜,减粘剂的加入量为胶乳总固体物质量的１．３％。     

120 m3 PVC聚合釜釜体制造工艺

120m3PVC聚合釜是国内首台采用分析设计标准设计、制造的大型设备。介绍了该聚合釜在加工制造过程中所采用的双面复合钢板的成型、焊接,焊缝表面喷丸处理,封头热压成型等工艺的特点,这与常规反应釜制造工艺不同。     

Printability of elastomer latex for additive manufacturing or 3D printing

Additive manufacturing, sometimes referred to as 3D printing is a new, rapidly developing technology which has the potential to revolutionize fabrication of certain high value, complex products. Until now conventional elastomers have not been widely used in the additive manufacturing process. The goal of our work was to determine the feasibility of additive manufacturing using ink jet printing of elastomeric latex materials. Particle size, viscosity, and surface tension were measured for five different latex materials—poly(2‐chloro‐1,3‐butadiene), carboxylated styrene‐butadiene rubber, carboxylated butadiene‐acrylonitrile copolymer, natural rubber, and prevulcanized natural rubber. The XSBR latex was predicted as the one most likely to be printable. Printing trials carried out with the XSBR as the ink proved it to be printable, although technical problems of agglomeration and print head clogging need to be addressed and both the material and process need to be optimized for consistent printing to be achieved. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42931.     

Modelling the zero shear viscosity of bimodal high solid content latex: Calculation of the maximum packing fraction

Different rheological tests were performed on monodisperse polystyrene latices and mixtures of two different latices with different particle sizes. A critical volume fraction φ_c was defined for each of the latices. Subsequently, a method based on the estimation of the porosity of a bed of randomly placed spherical particles was adapted to allow us to define the maximum packing fraction for any bimodal system. This method can be used for any ratio of particle diameter and volume fraction for the two populations provided one has knowledge of the critical volume fractions of related monodisperse latices (see Pishvaei et al., 2005. Polymer 46, 1235-1244). The model was tested experimentally, and rheological tests allowed us to validate the values of the critical volume fraction (φ_c) of different bimodal latices. A master curve of viscosity vs. polymer concentration was obtained using the concept of reduced volume fraction. The results prove that we can predict the viscosity of multimodal systems from the knowledge of monomodal packing fraction.     

羧基丁腈胶乳在20m~3釜的工业放大研究

主要考察了羧基丁腈胶乳在工业放大中引发剂的用量及其加入方式、反应前期温度、搅拌转速等因素对聚合过程及胶乳稳定性的影响。结果表明 :在 2 0m3 釜上引发剂的使用量仅为小试的5 0 %～ 60 % ,且引发剂量减少及加入时间延长 ,使聚合稳定性增加 ,设备操作周期延长 ;反应初期温度以1 5± 2℃为宜 ;反应转化率 <70 % ,搅拌器采用 1 0 0r/min转速 ,转化率≥ 70 % ,搅拌器采用 75r/min转速 ,可有效减少胶乳的凝胶量 ,提高胶乳质量。     

The effect of solid content on latex coalescence and film formation: Steady-state energy transfer study with fluorescence labeled polymers

The steady-state fluorescence technique was used to examine the healing and interdiffusion of polymer molecules as a function of solid content during annealing of latex films above the glass transition (T_g). Films were prepared from a mixture of naphthalene (N)- and pyrene (P)-labeled poly(methy methacrylate) (PMMA) latex particles. Above T_g, interdiffusion of polymer chains was observed by detecting the steady-state energy transfer from excited naphthalene to pyrene molecules. Various latex films with different latex content were used to measure the critical occupation percent for the reliable steady-state fluorescence measurements. Diffusion activation energies in these latex films were measured and found to be around 30 kcal/mol, which was attributed to the backbone motion of PMMA chains. © 1996 John Wiley & Sons, Inc.