Use of a sulphur or phosphorous-containing polymer as a processing aid in a polyvinyl chloride polymer composition

A suspension polymerisation reaction composition for synthesising a polyvinyl chloride polymer comprising;

• a continuous phase in which is dispersed droplets of one or more monomers to be polymerised;
• one or more primary suspending agents;
• a sulphur or phosphorous-containing polymer comprising:
• (i) residues of at least one ester-containing monomer, the ester-containing monomer(s) comprising one polymerisable carbon-carbon double bond per monomer and an ester group, and
• (ii) one or more residues of:
• (a) at least one monomer comprising a sulfonate, sulfonic acid, sulfonic ester, sulfonamide or sulfonyl halide group (or a salt or ester thereof), the monomer(s) comprising a sulfonate, sulfonic acid, sulfonic ester group, sulfonamide or sulfonyl halide group (or a salt or ester thereof) comprising one polymerisable carbon-carbon double bond per monomer and a sulfonate, sulfonic acid, sulfonic ester, sulfonamide or sulfonyl halide group (or a salt or ester thereof), or
• (b) at least one monomer of:
• where P is phosphorous, O is oxygen, at least one of X, Y and Z comprises at least one (and optionally only one) polymerisable carbon-carbon double bond, and
• at least one of X, Y and Z comprises OH, or a salt or ester thereof;
• the sulphur or phosphorous-containing polymer optionally being partially hydrolysed such that a proportion of said ester groups form alcohol groups, the degree of hydrolysis of the polymer being from 0 to 60 mol %;
• wherein said sulphur or phosphorous-containing polymer is made by emulsion polymerisation, and is added to the suspension polymerisation reaction mixture comprising vinyl chloride, which is reacted to form the polyvinyl chloride polymer;
• and
• wherein said sulphur or phosphorous-containing polymer comprises a seed;
• the sulphur or phosphorous-containing polymer providing processing aid properties to the polyvinyl chloride polymer.

A method of making a polyvinyl chloride polymer using suspension polymerisation, the method comprising:

• polymerising one or more monomers in the presence of a sulphur or phosphorous-containing polymer, the sulphur or phosphorous-containing polymer providing processing aid properties to the polyvinyl chloride polymer;
• wherein the sulphur or phosphorous-containing polymer comprises:
• (i) residues of at least one ester-containing monomer, the ester-containing monomer(s) comprising one polymerisable carbon-carbon double bond per monomer and an ester group, and
• (ii) one or more residues of:
• (a) at least one monomer comprising a sulfonate, sulfonic acid, sulfonic ester, sulfonamide or sulfonyl halide group (or a salt or ester thereof), the monomer(s) comprising a sulfonate, sulfonic acid, sulfonic ester group, sulfonamide or sulfonyl halide group (or a salt or ester thereof) comprising one polymerisable carbon-carbon double bond per monomer and a sulfonate, sulfonic acid, sulfonic ester, sulfonamide or sulfonyl halide group (or a salt or ester thereof), or
• (b) at least one monomer of:
• where P is phosphorous, O is oxygen, at least one of X, Y and Z comprises at least one (and optionally only one) polymerisable carbon-carbon double bond, and
• at least one of X, Y and Z comprises —OH, or a salt or ester thereof;
• the sulphur or phosphorous-containing polymer optionally being partially hydrolysed such that a proportion of said ester groups form alcohol groups, the degree of hydrolysis of the polymer being from 0 to 60 mol %;
• wherein said sulphur or phosphorous-containing polymer is made by emulsion polymerisation, and is added to the suspension polymerisation reaction mixture comprising vinyl chloride, which is reacted to form the polyvinyl chloride polymer;
• and
• wherein said sulphur or phosphorous-containing polymer comprises a seed.

A method of processing a polyvinyl chloride polymer composition, the method comprising:

• providing a polyvinyl chloride polymer composition comprising a processing aid comprising a sulphur or phosphorous-containing polymer, and
• processing said polyvinyl chloride polymer composition;
• wherein the sulphur or phosphorous-containing polymer comprises:
• (i) residues of at least one ester-containing monomer, the ester-containing monomer(s) comprising one polymerisable carbon-carbon double bond per monomer and an ester group, and
• (ii) one or more residues of:
• (a) at least one monomer comprising a sulfonate, sulfonic acid, sulfonic ester, sulfonamide or sulfonyl halide group (or a salt or ester thereof), the monomer(s) comprising a sulfonate, sulfonic acid, sulfonic ester group, sulfonamide or sulfonyl halide group (or a salt or ester thereof) comprising one polymerisable carbon-carbon double bond per monomer and a sulfonate, sulfonic acid, sulfonic ester, sulfonamide or sulfonyl halide group (or a salt or ester thereof), or
• (b) at least one monomer of:
• where P is phosphorous, O is oxygen, at least one of X, Y and Z comprises at least one (and optionally only one) polymerisable carbon-carbon double bond, and
• at least one of X, Y and Z comprises —OH, or a salt or ester thereof;
• the sulphur or phosphorous-containing polymer optionally being partially hydrolysed such that a proportion of said ester groups form alcohol groups, the degree of hydrolysis of the polymer being from 0 to 60 mol %;
• wherein said sulphur or phosphorous-containing polymer is made by emulsion polymerisation, and is added to a suspension polymerisation reaction mixture comprising vinyl chloride, which is reacted to form the polyvinyl chloride polymer;
• and
• wherein said sulphur or phosphorous-containing polymer comprises a seed.