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Polyvinyl acetate is also the raw material to make other polymers like: Polyvinyl alcohol −[HOCHCH 2]−: Polyvinyl acetate is partially or completely hydrolysed to give polyvinyl alcohol. This reversible saponification and esterification reaction was a strong hint for Hermann Staudinger in the formulation of his theory of macromolecules. [12]
This material has almost entirely replaced the use of cast iron for plumbing and drainage, being used for waste pipes, drainpipes, gutters and downspouts. PVC is known as having strong resistance against chemicals, sunlight, and oxidation from water.
The material is generally considered non-toxic. The EVA copolymer which is based on a medium proportion of VA (approximately 4 to 30%) is referred to as thermoplastic ethylene-vinyl acetate copolymer and is a thermoplastic elastomer material.
Like polystyrene itself, it is transparent and brittle. The copolymer has a glass transition temperature greater than 100 °C owing to the acrylonitrile units in the chain, thus making the material resistant to boiling water. It is structurally related to ABS plastic, where polybutadiene is copolymerised with SAN to give a much tougher material ...
Bringing water to its boiling point (about 100 °C or 212 F at sea level), is the oldest and most effective way since it eliminates most microbes causing intestinal disease, [19] but it cannot remove chemical toxins or impurities. [20]
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Hydrolytic stability in boiling water is excellent. Environments that deteriorate the polymers are high-temperature steam, concentrated sulfuric acid , and boiling caustic materials. Polar and bowlic LCPs are ferroelectrics , with reaction time order-of-magnitudes smaller than that in conventional LCs and could be used to make ultrafast switches.
Additionally, experts advise against microwaving or heating food in black plastic containers, as heat can exacerbate the leaching of harmful chemicals. Instead, transferring food to glass or ...