Polyvinyl chloride is

The monomer of the polymer $\left[ -CH_2-C(CH_3)_2- \right]_n$ is:

Identify the monomers needed for the synthesis of nylon $6,6$.

The monomers used in the preparation of Dextron are:

Which plastic is obtained from $CHCl_3$ as follows:
$CHCl_3$ $\xrightarrow[SbF_3]{HF} X$ $\xrightarrow{800^{\circ}C} Y$ $\xrightarrow{\text{Polymerisation}} \text{Plastic}$

What are $X$ and $Y$ in the following reaction?
$nClCH=CH_2 \xrightarrow{X} Y$