Question
Question: What are Vinylic alcohols?...
What are Vinylic alcohols?
Solution
We know that the polyvinyl alcohol (PVA) cannot be prepared by direct polymerization of vinyl alcohol. The synthesis is performed by the suspension polymerization of vinyl acetate. The process takes at about a temperature of 900∘Cand the pressure should be slow.
Complete answer:
PVA is a suitable polymer for biomedical applications due to its chemical properties and structure. The hydroxyl groups present make it soluble in water and in the body fluids. Synthesis of PVA is accomplished by several methods, one of the simplest and the easiest to do is by the polymerization of vinyl alcohol. But this cannot be done directly or there is a problem with this approach because vinyl alcohol is a very unstable chemical substance.
Vinyl alcohol which is also known as ethanol is a type of alcohol consisting of −OH group that is attached to a carbon (vinylic carbon or the aryl group) atom. It is the simplest of the enols. Its chemical formula is written as CH2CHOH. Vinyl alcohols are unstable and are isolated only in the form of their polymers or derivatives, esters or ether. It is usually produced by conducting the pyrolytic elimination process where water is removed from the ethylene glycol. PVA or the polyvinyl alcohol is a widely used coating industry polymer, which is commonly used as textile fiber coatings or as coatings for the pills.
Note:
Remember that the hydrolysis of PVAC into PVA implies the chemical modification where the acetate group leads to the alcohol group. Hydrolyzing PVAc by methanolysis is conventional. This method the PVAc is dissolved in the methanol and after that adding a base or an acid in order to catalyze the solution.