Present research is concerned with polymerization of various monomers on the surface of different clays. The monomers used were methyl methacrylate, vinyl chloride, acrylonitrile and N,N-dimethylaminoethyl methacrylate. The clays investigated were halloysite, bentonite, diatomaceous earth. A talc sample was also investigated for comparison. The clay surfaces were activated by acid treatment (50% H₂SO₄) and drying at 120℃ under vacuum, and the samples were subjected to one of the following three polymerization processes; 1)direct single step polymerization in which activated clay was dispersed directly into a polymerization mixture with an initiator such as AIBN and benzoyl peroxide, 2)redox polymerization in which N,N-dimethyl toluidine (or aniline) was adsorbed on the clay prior to the polymerization of monomers with a peroxide, and 3)solution polymerization in which solvents such as benzene, n-hexane and n-heptane were used as diluents, otherwise same to the above procedures. The observations we have made are as follows: i)Acid treatment activates and acidifies clay surface such that it improves polymerization yield as well as the amount of tightly bound polymers. ii)In solution polymerization the rate of polymerization dropped generally. When benzoyl peroxide was used as an initiator the best rate was observed in benzene compared with other solvent such as n-hexane. iii)Redox polymerization with N,N-dimethylaniline or copolymerization with monomer N,N-dimethylaminoethyl methacrylate with benzoyl peroxid as catalysts improved the polymer adhesion to the clay. iv)Polymer-coated clay containing around 8% of polymer did not sediment in water for prolonged time period (one month). v)Acrylonitrile failed to polymerize well on clay surface. vi)Talc was found to be more active in polymerization than clays. However the portion of bound polymer was small.

고령토에 개시제와 모노머를 흡수시켜 라디칼 중합하였다. 황산의 농도를 바꾸어가며 고령토를 산처리하여 개시제의 흡착능력을 비교하였으며 산처리한 고령토는 산성도와 표면적이 증가하였다. 고령토 표면에서의 라디칼 중합에 사용된 개시제로는 2,2-azobisisobutyronitrile(AIBN), N,N-dimethylaniline(DMA) 또는 N,N-dimethyltoluidine(DMTD)를 촉진제로 사용한 benzoyl peroxide(BPO) 등을 개시제로 사용하였으며 모노머는 methyl methacrylate(MMA), vinyl chloride(VCM), acrylonitrile(AN)을 사용하고 N,N-dimethylaminoethyl methacrylate(DMAEMA)를 comonomer로 5V/V% 넣어 고령토 표면 중합의 정도를 비교하였다. 고령토 표면에서의 MMA 중합은 단단계로는 잘 중합되었으나 용액중합의 경우는 MMA의 농도와 용매의 종류에 따라 크게 폴리머의 수득률에 차이가 생겼다. VCM 중합은 단단계 중합을 하였으며 중합조건을 바꾸어 가며 중합한 결과, 중합수율을 높이기 위해서는 고령토를 산처리하여 활성화시켜야 하고 반응기에 압력을 가하면서 온도를 높여주어야 하였다. Redox계로서 DMA와 모노머로서 DMAEMA를 사용하면 친수성인 고령토와 소수성인 폴리머 사이의 결합력이 크게 증가되었으며, 고령토 무게의 8% 정도만 폴리머가 덮어져 있어도 완전히 물에 뜰 정도로 고령토가 소수성 표면을 갖게 되었다. 활석은 고령토보다 중합이 잘 일어났으며, 규조토는 가장 중합이 잘 되었으나 폴리머와의 결합력이 작아 용매에 대부분 추출되었다.

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