It was investigated how the addition of a mixture of two water-soluble polymeric species affe-cted the state of encapsulation of pigments by soap-free emulsion polymerization. The pigments examined were disazo-yellow (Index number, PY17), phthalocyanine blue (Index number, PB 15 : 3), and carbon black (# 15), which had been predispersed in the aqueous solution of a sur-factant before the polymerization. The monomer used for the encapsulation was methyl metha-crylate. The surfactants added were hydroxy-propyl methyl cellulose (HPMC) and poly (vinyl alcohol) (PVA). In this experiment, the sate of encapsulation was mainly examined by the addition of PVA and HPMC with different degree of polymerization. It was found that the pigments were encapsulated better by the addition of the mixture of PVA and HPMC rather than the individual surfactants.
Inorganic silica capsule with cavity was prepared by utilizing a non-aqueous gelling agent derived from amino acid and tetraethoxysilane (TEOS). The non-aqueous gelling agent used was N-lauroyl-L-gultamic acid-α, γ-di-n-butylamide (LGBA). When ammonia water (pH = 13. 2) was added dropwise to the solution composed of LGBA, TEOS, n-decane (oil), and alco-hol having alkyl chain less than two, the hollow gel with TEOS trapped in its structure was formed at the interface between the solution and water. A heat treatment of this TEOS-trapped gel resulted in the formation of the silica porous capsule with cavity.
Gold particles were prepared in hexadecyltrimethylammonium chloride (HTAC) / water system by UV irradiation. At concentrations which exhibit rod-like HTAC micellar shape, rod-like gold particles were obtained at higher concentrations of HAuCl4 with increasing irradiation time. This result demonstrates the preparation of anisotropic gold particles using surfactant as template.