Dispersions of hybrid polyurethane particles are made using miniemulsion techniques. An isocyanate-terminated prepolymer and a monomer are mixed and dispersed in an aqueous phase to form a dispersion of droplets. All droplets are polymerized and chain-extended in one step to form hybrid particles containing a polyurethane and a polymer of the monomer. This process provides a simple method of making hybrid particles, in which particle size and the number of particles is controlled in the mixing step. The hybrid particles often have a core-shell morphology, with the polyurethane being concentrated in the shell and the polymer being concentrated in the center of the particle.
混合聚
氨酯颗粒的分散体是利用微型乳液技术制成的。将
异氰酸酯封端预聚物和单体混合并分散在
水相中,形成液滴分散体。所有液滴在一个步骤中聚合并扩链,形成含有聚
氨酯和单体聚合物的混合颗粒。这种工艺提供了一种制造混合颗粒的简单方法,在混合步骤中可以控制颗粒的大小和数量。混合颗粒通常具有核壳形态,聚
氨酯集中在颗粒的外壳中,而聚合物则集中在颗粒的中心。