摘要:
Compositions comprising at least one epoxy resin and/or reactive diluents, at least one hardener for the at least one epoxy resin, at least one curing indicator, wherein the color of the composition changes depending on the curing degree, a process for determining sufficient cure of a composition comprising providing a composition comprising at least one epoxy resin and a hardener for the epoxy resin, adding a curing indicator, applying curing conditions to the colored composition until the composition changes its color and use of polymeric colorants as curing degree indicator, wherein the curing indicator is a polymeric colorant consisting of chromophores which are chemically bound to polymers having reactive groups.
摘要:
Titanates of barium, strontium, or mixed barium and strontium consisting essentially of solid, non-aggregated particles having diameters ranging from 0.05 to 1 micron and a narrow particle size distribution expressed by the polydispersity index, dw/dn, not greater than 1.20, where dw is the weight average diameter and dn is the number average diameter, said particles being essentially perfectly spherical with a total mean axial ratio of at least 0.93. These titanates are prepared by a process which comprises precipitating of a peroxidic precursor having the same morphological characteristics of the titanates. The peroxidic precursor is obtained by heating an alkaline solution comprising a complex of a titanium compound with a peroxidic compound, an M.sup.2+ compound, wherein M is Ba, Sr or mixtures thereof, and a compound Z capable of complexing with the M.sup.2+ ion oxidizable by the peroxidic compound under the conditions of reaction to produce soluble decomposition products and provide a homogeneous precipitation of the peroxidic precursor comprising titanium and M.sup.2+. Subsequently the precursor is heated to a temperature of at least 100.degree. C. to obtain the corresponding titanate having the above-indicated morphological characteristics.
摘要:
Spherical particles having sizes below 1 .mu.m, or at maximum of 3.04 .mu.m, a narrow size size distribution consisting, or consisting essentially, of TiO.sub.2 coated by a uniform layer having a thickness up to 400 .ANG. consisting essentially .alpha.-, or .gamma.-Fe.sub.2 O.sub.3, or magnetite, or mixtures thereof, said particles being prepared by a process consisting, or consisting essentially, in the precipitation of the oxide from Fe (III) salt solutions on the surface of solid pre-formed TiO.sub.2 particles having a narrow size distribution and a number average diameter below 1 .mu.m or .ltoreq.3 .mu.m, the Fe (III) concentration being .ltoreq.40% by weight calculated on TiO.sub.2, the pH of the suspension ranging from 1.0 to 2.8, extremes excluded, by heating the suspensions to temperatures of from 80.degree. to 100.degree. C., and by aging them under such conditions for at least 30 minutes.
摘要翻译:尺寸小于1μm,或最大为3.04μm的球形颗粒,窄尺寸尺寸分布由基本上由厚度达400的均匀层涂覆的TiO 2组成或基本上由基本上由α-或γ- Fe 2 O 3或磁铁矿或其混合物,所述颗粒通过由具有窄尺寸分布的固体预形成TiO 2颗粒表面上的Fe(III)盐溶液中的氧化物沉淀而形成或基本上由其组成的方法制备 和数均平均直径小于1微米或 3微米,Fe(III)浓度为按TiO 2计算的40重量%,悬浮液的pH范围为1.0至2.8,不包括极限,由 将悬浮液加热至80℃至100℃的温度,并在此条件下老化至少30分钟。
摘要:
Compositions comprising at least one epoxy resin and/or reactive diluents, at least one hardener for the at least one epoxy resin, at least one curing indicator, wherein the colour of the composition changes depending on the curing degree, a process for determining sufficient cure of a composition comprising providing a composition comprising at least one epoxy resin and a hardener for the epoxy resin, adding a curing indicator, applying curing conditions to the coloured composition until the composition changes its colour and use of polymeric colourants as curing degree indicator, wherein the curing indicator is a polymeric colourant consisting of chromophores which are chemically bound to polymers having reactive groups.