Method for reducing wall fouling in vinyl chloride polymerization
AssigneeAir Products and Chemicals, Inc.
InventorBernard D. Bauman
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Abstract
This invention relates to an improvement for reducing the amount of wall fouling in the suspension polymerization of vinyl chloride. The improvement resides in wetting the reactor surface with a solution containing from 5 to 50 parts by weight of an alkali metal hydroxide prior to charging the vinyl chloride recipe to the reactor. Preferably, the surface of the resulting reactor is heated at a temperature of from 40.degree.-100.degree. C. prior to charging the recipe.
Claims5
In a suspension polymerication process wherein a recipe comprising vinyl chloride or a mixture of vinyl chloride and another vinyl monomer, water, a suspension agent, and a monomer soluble polymerization catalyst is charged to a stainless steel reactor at an intial pH above 6.0 and subsequently polymerized at an elevated temperature to produce a vinyl chloride containing polymer, the improvement for reducing wall fouling in said stainless steel reactor, which comprises:
- wetting the internal reactor surface with a solution comprising from about 10-50% by weight of an alkali metal hydroxide;
- and
- heating the wet reactor surface to a temperature from 40.degree.-100.degree. C. for a period of at least 5 minutes prior to charging the recipe to the reactor.
Dependencies are inferred from the claim text.