合成了含氢聚甲基硅氧烷/聚丙烯酸酯共聚乳液.研究了聚合工艺、配方组成及操作方式对聚合稳定性、动力学、乳液的粒径分布和产物性能的影响.采用部分预乳化单体滴加法(工艺A)和部分纯单体滴加法(工艺B)两种工艺,聚硅氧烷采用高速预乳化...合成了含氢聚甲基硅氧烷/聚丙烯酸酯共聚乳液.研究了聚合工艺、配方组成及操作方式对聚合稳定性、动力学、乳液的粒径分布和产物性能的影响.采用部分预乳化单体滴加法(工艺A)和部分纯单体滴加法(工艺B)两种工艺,聚硅氧烷采用高速预乳化滴加进料方式.用COULTER LS 粒径仪和Nicolet 傅立叶变换红外光谱仪分别测定共聚乳液的粒径分布和产物的结构.研究结果表明,采用A、B两种工艺均能得到平均粒径为0.101~0.103(m的单峰窄分布共聚乳液,并能有效地将含氢聚硅氧烷引入到共聚物大分子中.含氢聚硅氧烷的引入量为3%(质量)时,共聚物涂膜具有柔软、滑爽和强度高等优点.展开更多
A novel waterborne epoxy curing agent was prepared using 3-glycidoxypropyl trimethoxysilane （GPTMS） as a termination agent of adduct, which was synthesized by triethylene tetramine （TETA） and liquid epoxy resin （...A novel waterborne epoxy curing agent was prepared using 3-glycidoxypropyl trimethoxysilane （GPTMS） as a termination agent of adduct, which was synthesized by triethylene tetramine （TETA） and liquid epoxy resin （E-51）. The effects of the reaction temperature and time on the synthesis process were investigated experimentally. The particle size and the distribution of water dispersion of the curing agent were measured by dynamic light scattering（DLS）. The structure of the products was characterized by Fourier transform infrared spec-trometer （FTIR） and ^1H-nuclear magnetic resonance （^1H NMR）. The properties of the synthesized curing agent and the epoxy resin film cured by it were also measured. The results showed that the appropriate temperature for the synthesis of adduct was at 65-75℃ and the reaction time was 4-5h, and that the suitable reaction temperature of curing agent synthesis was 75-85℃ and the reaction time was 3-4h. When the mass ratios of GPTMS and acetic acid were 3%-5% and 5%-10% respectively, the hardness, water resistance and adhesion of the cured film were improved significantly.展开更多
以磷酸三钙(Tripotassium Phosphate or TCP)为苯乙烯悬浮聚合的分散剂,实验研究了分散剂的用量、表面活性剂的浓度、油水比、电介质盐及搅拌转速等因素对液滴聚合增长的影响。着重分析在无机分散剂存在下,液滴分散、合一的特点。从而...以磷酸三钙(Tripotassium Phosphate or TCP)为苯乙烯悬浮聚合的分散剂,实验研究了分散剂的用量、表面活性剂的浓度、油水比、电介质盐及搅拌转速等因素对液滴聚合增长的影响。着重分析在无机分散剂存在下,液滴分散、合一的特点。从而关联出了瞬间液滴平均直径的准数方程:(d)_(32)/D=1.86(Ф)^(0.388)We^(-0.444)(μ_d/μ_c)^(0.103)展开更多
A novel novolac curing agent containing both naphthalene and dicyclopentadiene (DCPD) moieties was prepared to produce a highly heat-resistant cured polymer network. The chemical structure was characterized using Four...A novel novolac curing agent containing both naphthalene and dicyclopentadiene (DCPD) moieties was prepared to produce a highly heat-resistant cured polymer network. The chemical structure was characterized using Fourier transform infrared spectroscopy, nuclear magnetic resonance, mass spectrometry, and gel permeation chro-matography analyses. The thermal properties of the resulting polymer from diglycidyl ether of bisphenol A epoxy resin cured with the novel curing agent were evaluated using dynamic mechanical thermal analysis and thermogra-vimetric analysis. Compared with the conventional curing agent, the resulting polymer cured with naphtha-lene/DCPD navolac shows considerable improvement in heat resistant properties such as higher glass transition temperature (Tg) and thermal stability. The result also shows better moisture resistance because of the hydrophobic nature of naphthalene/DCPD structure.展开更多
文摘合成了含氢聚甲基硅氧烷/聚丙烯酸酯共聚乳液.研究了聚合工艺、配方组成及操作方式对聚合稳定性、动力学、乳液的粒径分布和产物性能的影响.采用部分预乳化单体滴加法(工艺A)和部分纯单体滴加法(工艺B)两种工艺,聚硅氧烷采用高速预乳化滴加进料方式.用COULTER LS 粒径仪和Nicolet 傅立叶变换红外光谱仪分别测定共聚乳液的粒径分布和产物的结构.研究结果表明,采用A、B两种工艺均能得到平均粒径为0.101~0.103(m的单峰窄分布共聚乳液,并能有效地将含氢聚硅氧烷引入到共聚物大分子中.含氢聚硅氧烷的引入量为3%(质量)时,共聚物涂膜具有柔软、滑爽和强度高等优点.
文摘A novel waterborne epoxy curing agent was prepared using 3-glycidoxypropyl trimethoxysilane （GPTMS） as a termination agent of adduct, which was synthesized by triethylene tetramine （TETA） and liquid epoxy resin （E-51）. The effects of the reaction temperature and time on the synthesis process were investigated experimentally. The particle size and the distribution of water dispersion of the curing agent were measured by dynamic light scattering（DLS）. The structure of the products was characterized by Fourier transform infrared spec-trometer （FTIR） and ^1H-nuclear magnetic resonance （^1H NMR）. The properties of the synthesized curing agent and the epoxy resin film cured by it were also measured. The results showed that the appropriate temperature for the synthesis of adduct was at 65-75℃ and the reaction time was 4-5h, and that the suitable reaction temperature of curing agent synthesis was 75-85℃ and the reaction time was 3-4h. When the mass ratios of GPTMS and acetic acid were 3%-5% and 5%-10% respectively, the hardness, water resistance and adhesion of the cured film were improved significantly.
文摘以磷酸三钙(Tripotassium Phosphate or TCP)为苯乙烯悬浮聚合的分散剂,实验研究了分散剂的用量、表面活性剂的浓度、油水比、电介质盐及搅拌转速等因素对液滴聚合增长的影响。着重分析在无机分散剂存在下,液滴分散、合一的特点。从而关联出了瞬间液滴平均直径的准数方程:(d)_(32)/D=1.86(Ф)^(0.388)We^(-0.444)(μ_d/μ_c)^(0.103)
文摘A novel novolac curing agent containing both naphthalene and dicyclopentadiene (DCPD) moieties was prepared to produce a highly heat-resistant cured polymer network. The chemical structure was characterized using Fourier transform infrared spectroscopy, nuclear magnetic resonance, mass spectrometry, and gel permeation chro-matography analyses. The thermal properties of the resulting polymer from diglycidyl ether of bisphenol A epoxy resin cured with the novel curing agent were evaluated using dynamic mechanical thermal analysis and thermogra-vimetric analysis. Compared with the conventional curing agent, the resulting polymer cured with naphtha-lene/DCPD navolac shows considerable improvement in heat resistant properties such as higher glass transition temperature (Tg) and thermal stability. The result also shows better moisture resistance because of the hydrophobic nature of naphthalene/DCPD structure.
