保定市分散剂厂

分散剂初步筛选

Preliminary screening of dispersants

在选择分散剂时，必须要根据体系极性选择合适极性范围的分散剂，并根据使用颜料的种类和要求选择锚定基团的种类和数量。也要根据配方设计方案来决定如何选择分散剂，如厚浆型或非厚浆型；混色研磨还是单色研磨；通用色浆还是专用色浆等，可能要采用不同类型的分散剂。

When choosing dispersant, it is necessary to select dispersant with appropriate polarity range according to the polarity of the system, and choose the type and quantity of anchoring groups according to the type and requirement of the pigments used. It is also necessary to decide how to choose dispersants according to the formulation design, such as thick or non-thick paste, mixed or monochrome grinding, general or special color paste, and so on. Different types of dispersants may be used.

使用高分子型分散剂时，还需要注意分散剂必须与树脂基料相容，如果相容性不佳，分散剂链段缠绕，其锚定基团难以吸附到颜料表面，并且空间位阻作用丧失，对颜料的分散稳定效果变差。测试分散剂与树脂之间的相容性时，可取透明容器，将8份树脂混入2份助剂，用手工搅拌混合均匀（也可加入适量溶剂），观测其混合液是否清澈透明，是否凝胶；把混合液滴在聚酯塑料膜片上摊平，自干或烘干观察漆膜的透明性。笔者在筛选分散剂时，相容性不好而分散效果很好的实例，在高分子型分散剂中几乎没有碰到。

When using macromolecule dispersant, attention should also be paid to the compatibility of dispersant with resin base material. If the compatibility is not good and the dispersant chain is winded, the anchoring group of dispersant is difficult to adsorb to the surface of the pigment, and the steric hindrance effect is lost, which makes the dispersion and stabilization effect of the pigment worse. When testing the compatibility between dispersant and resin, it is advisable to use transparent container, mix 8 parts of the resin into 2 auxiliaries, stir it evenly with hand, and mix evenly (or add proper amount of solvent) to observe whether the mixture is clear and transparent, whether it is gel or not. Sex. In the screening of dispersants, there are few examples of poor compatibility and good dispersion effect, which are rarely encountered in polymer dispersants.

在初步筛选分散剂时，还要注意分散剂与树脂之间有无反应性，这通常为大家所忽略。有些分散剂如高分子酰胺型分散剂会与某些树脂如环氧树脂产生反应，从而影响色浆的贮存稳定性。分散剂A及B均与环氧树脂E44产生反应，颜色由淡黄变为深蓝色。分散剂C与D甚至与环氧树脂E44产生了固化而丧失了流动性。

In the preliminary screening of dispersants, attention should also be paid to the reactivity between dispersants and resins, which is often overlooked. Some dispersants, such as macromolecule amide dispersants, react with some resins, such as epoxy resin, thus affecting the storage stability of color paste. Dispersants A and B react with epoxy resin E44, and the color changes from light yellow to dark blue. Dispersants C and D even cured with epoxy resin E44 and lost fluidity.

有几个简单的方法，可以初步判断分散剂在该体系中的表现，如采用重力沉降法初筛分散剂，可将颜料、分散剂、树脂稀溶液简单高搅后观察沉降速度，悬浮情况等；沉降越慢的分散剂可能越适用。降黏能力测试法则是测量不同分散剂对同样颜料树脂浆高速搅拌后的黏度降低情况，每添加一次测一次黏度，黏度越低的分散剂可能越适用（受控絮凝类分散剂除外）。采用丹尼尔流动法初步筛选分散剂，湿流点差越小的分散剂越适用。

There are several simple methods to judge the performance of dispersant in this system. For example, the dispersant can be screened by gravity sedimentation method, and the settling speed and suspension of pigments, dispersants and resin dilute solution can be observed after simple and high stirring. The slower the settling, the more suitable the dispersant may be. Viscosity reduction test method is to measure the viscosity reduction of different dispersants after high-speed mixing of the same pigment resin slurry. The lower the viscosity, the more suitable the dispersant is (except controlled flocculant dispersants). Daniel flow method was used to screen initially dispersants. The smaller the difference of wet flow point, the more suitable the dispersants were.