Method for manufacturing thermoplastic poly(vinyl alcohol) derivative in a melt state reaction and products thereof

A method for manufacturing thermoplastic poly(vinyl alcohol) derivative (CMP1;

• CMP2;
• CMP3) which contains pendant chains which end into vinyl groups, the method comprising:
• heating (HT1) thermoplastic poly(vinyl alcohol) (PVA1) having hydroxyl groups, wherein the thermoplastic poly(vinyl alcohol) (PVA1) has been dried and has a degree of hydrolysis in the range of 65 to 90 mol-%, and
• admixing (AD1) reagent (RGT1) with the thermoplastic poly(vinyl alcohol) (PVA1), wherein said reagent (RGT1) is an organic acid anhydride (AH1;
• AH2;
• AH3;
• AH4;
• AH5) having at least a chain which has a catenated carbon structure of at least 4 carbon atoms and which ends into a vinyl group,
• such that a mixture (MXT1) is obtained which contains molten thermoplastic poly(vinyl alcohol) (PVA1) having hydroxyl groups and organic acid anhydride (AH1;
• AH2;
• AH3;
• AH4;
• AH5) which contains chains which end into vinyl groups, and
• mixing (MR1) the mixture (MXT1) at a temperature which is above the melting point of the mixture (MXT1), thereby causing a reaction in a melt state, wherein at least some of the organic acid anhydride (AH1;
• AH2;
• AH3;
• AH4;
• AH5) reacts with the hydroxyl groups of the thermoplastic poly(vinyl alcohol) (PVA1) in an ester bond forming condensation reaction,
• such that reaction product (PROD1) is formed which contains
• carboxylic acid residue (RD1;
• RD2;
• RD3) of the ester bond forming condensation reaction, wherein at least some of said carboxylic acid residue contains chains which end into vinyl groups, and
• thermoplastic poly(vinyl alcohol) derivative (CMP1;
• CMP2;
• CMP3) which contains ester bonded pendant chains of which at least some end into vinyl groups.