PVA thiaj rau hais tias noj nrog qab nyob: polymerization thiab alcoholysis. Rau zoo, vinyl acetate monomer (VAM) muaj emulsion los yog solution polymerization. Ntau emulsion polymerization, VAM, ntawv, thiab emulsifiers muaj micelles los yuav tshaj initiators ib tug persulfates muaj polymerization, tau polyvinyl acetate (PVAc) latex particles. Solution polymerization mus organic solvents (e.g., methanol) los yuav cas VAM, tau PVAc nrog homogeneous solution. Rau zoo, PVAc muaj alcoholysis nrog methanol thiab sodium hydroxide los yuav cas catalyst, muaj acetate groups los yuav tshaj hydroxyls tau PVA. Qhov cov hydrolysis (DH) muaj yooj ib tug reaction time thiab catalyst amount—higher DH (e.g., 99%) tau water-resistant PVA, thiab lower DH (e.g., 88%) muaj cold-water solubility. Cov process tsum nrog washing, drying, thiab milling los powders los flakes.
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