\(CaCO_3-^{t^o}\rightarrow CaO+CO_2\\ CaO+3C-^{t^o}\rightarrow CaC_2+CO\\ CaC_2+2H_2O\rightarrow C_2H_2+Ca\left(OH\right)_2\\2 C_2H_2-^{t^o,xt}\rightarrow CH\equiv C-CH=CH_2\\ CH\equiv C-CH=CH_2+H_2-^{t^o,Pd/PbCO_3}\rightarrow CH_2=CH-CH=CH_2\\ nCH_2=CH-CH=CH_2-^{t^o,p,xt}\rightarrow\left(-CH_2CH=CH-CH_2-\right)_n\)
\(a.nCH_2=CH_2-^{t^o,p,xt}\rightarrow\left(-CH_2-CH_2-\right)_n\\ b.nCH_2=C\left(CH_3\right)_2-^{t^o,p,xt}\rightarrow\left(-CH_2-C\left(CH_3\right)_2-\right)_n\\ c.nCH_2=CHCl-^{t^o,p,xt}\rightarrow\left(-CH_2-CHCl-\right)_n\\ d.nCH_2=CH-CH=CH_2-^{t^o,p,xt}\rightarrow\left(-CH_2CH=CH-CH_2-\right)_n\\ e.nCH_2-C\left(CH_3\right)-CH=CH_2-^{t^o,p,xt}\rightarrow\left(-CH_2-C\left(CH_3\right)=CH-CH_2-\right)_n\\ \)