Polyvinylacetate

pva synthesis

1. By Engineer Nathan.J . Chifamba B-tech Hons Chemical and Process Systems Engineering (Harare Institute of Technology ,Zimbabwe) M-Tech Polymer Science and Technology (Amity University Gurgaon India) Polymer Technology Presentation ( Dr Nidhi Goel lecturer) 22/12/2016

2. Polyvinyl Acetate

3. Brief History Poly(vinyl acetate) was discovered in Germany in 1912 by Fritz Klatte . The monomer, vinyl acetate, was first produced on an industrial scale by addition of acetic acid to acetylene with a mercury(I) salt but it is now primarily made by palladium catalyzed oxidative addition of acetic acid to ethylene . Polyvinyl acetate is prepared by polymerization of vinyl acetate monomer (free radical vinyl polymerization of the monomer vinyl acetate).

4. INTRODUCTION it is a colorless , nontoxic thermoplastic resin prepared by the polymerization of vinyl acetate. Polyvinyl acetate (PVAC) It is one of the most widely used water-dispersed resins . Polyvinyl acetate water-based emulsions have been used as latex house paints, artists' media (since 1945), and common household white glues .. Poly(vinyl acetate) (PVA, PVAc , poly( ethenyl ethanoate ) It is commonly referred to as wood glue, white glue, carpenter's glue, school glue, Elmer's glue in the US, or PVA glue) It is an aliphatic rubbery synthetic polymer with the formula (C 4 H 6 O 2 ) n . It belongs to the polyvinyl esters family with the general formula -[RCOOCHCH 2 ]-.

5. PROPERTIES Under alkaline conditions, boron compounds such as boric acid or borax cause the polymer to cross-link. A number of microorganisms can degrade polyvinyl acetate(fungi and algae). Sets by the removal of water due to evaporation or absorption into a substrate. Have good weather resistance W ithstand water, grease, oil, and petroleum fuels degradation. good biodegradation resistance poor resistance to creep under load. Softens at 30-45C Soluble in benzene, chloroform, methanol, acetone, butyl acetate Insoluble in ligroin, diethyl ether, butanol , turpentine, water, oils Can absorb 3-5% water when immersed for 16 hours at 60 C . Burns with a dark yellow flame that smells of acetic acid . Combustible.

6. Uses PVA water-based emulsions have been used as latex house paints. Making commonly used household white glues. Making wood glue. Makin paper glue. Adhesives. Glues for porous material. Used as a primer for drywall and other substrates. As a mortar additive.

7. 7 Mechanism (free radical Polymerization)

8. Free Radical Mechanism

9. Mechanism Continued 9

10. Any Questions!!!!