<h3 id="successpolymerlecture-2success"><Success>Polymer(lecture-2)</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-010-0031.2.jpg"></p> </div>

<h3 id="successclassification-of-polymerssuccess"><Success>Classification of polymers</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <ol> <li>Based on sources</li> <li>Based on structures -</li> <li>Based on modes of polymerization: (Composition/Structure)</li> </ol> <p><ins>Addition</ins>: Two or more molecules combine to form one large molecule. $$\mathrm{CH}_2=\mathrm{CH}_2+\mathrm{Cl}_2 \rightarrow \mathrm{CH}_2 \mathrm{Cl}-\mathrm{CH}_2 \mathrm{Cl}$$</p> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-034-0285.6.jpg"></p> </div>

<h3 id="successhomo-polymerssuccess"><Success>Homo polymers</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <ul> <li>$\left.n \mathrm{CH}_2=\mathrm{CH}-\mathrm{CH}=\mathrm{CH}_2 \rightarrow [-\mathrm{CH}_2-\mathrm{CH}=\mathrm{CH}-\mathrm{CH}_2 -\right]_n$</li> </ul> <p>(1,3-Butadiene)</p> <ul> <li>$$\begin{aligned} & n \quad \mathrm{CH}_2=\mathrm{CHCl} \ \end{aligned}\xrightarrow{Polymerization} [-\mathrm{CH}_2-\mathrm{CHCl-}]_n $$poly(vinyl chloride) PVC</li> </ul> <p>$\mathrm{Na}$</p> <ul> <li>Homo polymers</li> </ul> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/dd0926db-fd9a-4fec-2096-0d014cfe8500/public" width="100%" > <!--<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/f9490f7e-ce4d-4685-0a65-1f75580df400/public" width="80%" >--> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-56.jpg"></p> </div>

<h3 id="successcondensation-polymerssuccess"><Success>Condensation Polymers</Success></h3> <div style='float: left; width:99%;text-align:left;font-size:26px'> <p><strong>Condensation reactions:</strong></p> <ul> <li>Two or more molecules react to produce one molecule along with production of small molecule like water, methanol $$ \begin{aligned} & \mathrm{CH_3} \mathrm{COOH}+\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{OH} \ & \longrightarrow \mathrm{CH}_3-\mathrm{COOCH}_2 \mathrm{CH}_3+\mathrm{H}_2 \mathrm{O} \ & \text { Ethylacetate } \ & \end{aligned} $$</li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-57.jpg"></p> </div>

<h3 id="successnylonsuccess"><Success>Nylon</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <p><strong>Nylon 6,6.</strong></p> <ul> <li> <p>$nH_2N-(CH_2)_6-NH_2 (hexamethylene \hspace{1mm} diamine)+nHOOC-(CH_2)_4-COOH (adipic \hspace{1mm} acid) \rightarrow [-HN-(CH_2)_6-NH-CO-(CH_2)_4-CO-]_n+(2n-1)H_2O$ (Polyamide hexamethylene adipimide) Nylon 6,6</p> </li> <li> <p>$nH_2N-(CH_2)_5-COOH \rightarrow [-HN-(CH_2)_5-CO-]_n+(2n-1)H_2O$ Nylon 6</p> </li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-129-1106.4.jpg"></p> </div>

<h3 id="successpoly-ethylene-teraphthalatssuccess"><Success>Poly ethylene teraphthalats</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:25px'> <p><strong>PET</strong></p> <ul> <li>$nHOOC-C_6H_4-COOH+nHO-CH_2-CH_2-OH \rightarrow [-OC-C_6H_4-COO-CH_2-CH_2-O-]_n(Poly \hspace{1mm} ethylene \hspace{1mm} teraphthalats) +(2n-1)H_2O (HOMO)$</li> <li>$nHOOC-C_6H_4-COOH+ \frac{n}{2} OH-CH_2-CH_2-OH+ \frac{n}{2} OH-CH_2-CH_2-CH_2-CH_2-OH$ $\rightarrow$ Poly (fethylene-co-butylene terephthalate) (Copolymer)</li> </ul> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/68170137-9034-49a2-f464-d6dc05b9e500/public" width="60%" > </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-168-1407.6.jpg"> <img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-56.jpg"></p> </div>

<h3 id="successmechanism-of-polymerizationsuccess"><Success>Mechanism of polymerization</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <h4 id="4-based-on-mechanism-of-polymerization">4. Based on mechanism of polymerization</h4> <p>$CH_2=CH-C_6H_5 \rightarrow [-CH_2-CH-]_n-C_6H_5-$</p> <ul> <li>Radical cation anion</li> <li>Initiation</li> </ul> <p>$CH_2=CH-R+ I^.$ $\rightarrow$ $I-CH_2-C^* H-R $ + $CH_2=CH-R$ $\rightarrow$ $I-CH_2-CH(R)-CH_2-C^{*}H-R$</p> <ul> <li>Propagation</li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-190-1652.4.jpg"></p> </div>

<h3 id="successterminationsuccess"><Success>Termination</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <ul> <li> <p>Polymers are produced by addition of monomers at the end of growing chain $\rightarrow$ Chain-growth polymerization, Chain-growth polymers</p> </li> <li> <p>Termination</p> </li> <li> <p>4-Based on mechanism of polymerization</p> </li> <li> <p>Radical cation anion</p> </li> <li> <p>Propagation</p> </li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-228-1905.6.jpg"> <img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-190-1652.4.jpg"></p> </div>

<h3 id="successradical-chain-polymerizationsuccess"><Success>Radical chain polymerization</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <p>$$I^.$$</p> <ul> <li> <p><strong>Thermal initiators:</strong> covalent bonds which can be homolytically cleaved into the radicals by heating</p> </li> <li> <p>$\phi-CO-O-O-CO-\phi(benzoyl \hspace{1mm} peroxide) \xrightarrow {\Delta} 2\phi-CO-O^. \rightarrow 2\phi^.+2CO_2$</p> </li> <li> <p>t-butyle peroxide $(CH_3)_3-C-O-O-C-(CH_3)_3$</p> </li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-58.jpg"></p> </div>

<h3 id="successacetyl-peroxidesuccess"><Success>Acetyl peroxide</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <p><strong>Acetyl peroxide</strong></p> <p>$CH_3-CH_2-CO-O-O-CH_2-CH_3$</p> <ul> <li>2,2’- Azobisisobutyronitrile (AIBN)</li> </ul> <p>$(CH_3)_2CN^-C-N=N-C-(CH_3)_2CN^-$</p> <p>$X \xrightarrow {\Delta} 2I^. \xrightarrow {CH_2=CH-R} I-CH_2-C^.H-R$</p> <p>Propagation</p> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-59.jpg"></p> </div>

<h3 id="successterminationsuccess-1"><Success>Termination</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <ul> <li>Termination</li> </ul> <p>$-CH_2-C^.H_2-$</p> <p>$-CH_2-CH_2-$</p> <p>$-CH_2-CH_2-CH_2-CH_2-$ coupling</p> <p>$-CH=CH_2$</p> <p>$-CH_2-CH_3$ disproportionation</p> <ul> <li>Chain - growth</li> <li>Initiation → propagation → Termination</li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-60.jpg"></p> </div>

<h3 id="successstep-growth-polymerssuccess"><Success>Step-growth polymers</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:25px'> <p><strong>Polyester formation</strong></p> <ul> <li> <p>$nHO-R-OH (monomer \hspace{1mm} A)+ nHOOC-R^{’}-COOH (monomer \hspace{1mm} B) \rightarrow -CO-O-+H_2O \rightarrow OH-R-O-CO-R^{’}-COOH$ (dimer)</p> </li> <li> <p>Dimer $\hspace{1mm} + \hspace{1mm}$ monomer $\rightarrow$ trimer</p> </li> <li> <p>Dimer $\hspace{1mm} + \hspace{1mm}$ Dimer $\rightarrow$ tetramer</p> </li> </ul> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/16fa1a9c-abe0-4727-ef45-b51491dabc00/public" width="50%" > </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-61.jpg"></p> </div>

<h3 id="successpolymersuccess"><Success>Polymer</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <ul> <li>Generally (not always)</li> <li>Addition $\leftrightarrow$ chain-growth</li> <li>Condensation $\leftrightarrow$ step-growth</li> <li>Exception (one example)</li> <li>$HO-R-OH (diol) + OCN^–R^{’}-NCO (diisocyanate) \rightarrow [-O-R-O-CO-N-R^{’}-NH-CO-] (polyurethane)$</li> <li>Addition Step-growth</li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-62.jpg"></p> </div>

<h3 id="successbased-on-mechanical-behaviorsuccess"><Success>Based on mechanical behavior</Success></h3> <div style='float: left; width:100%;text-align:left;font-size:30px'> <!--**5. Based on mechanical behavior**--> <ul> <li>Stress: Force/area = F/A</li> <li>Strain: change in diamension/original length = $\Delta$ L/L</li> </ul> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/b922d0aa-b585-4d7e-e3ff-8d5ff49afa00/public" width="30%"> <ul> <li>$\frac{\text { Stress }}{\text { strain }}=$ Modulus (Resistance to deformation) Elastomers high elongation $\geqslant 5-10$ times $\geqslant$ 500-1000% Reversine Modulus is low</li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-63.jpg"></p> </div>

<h2 id="successthank-yousuccess"><Success>Thank you</Success></h2> <div style='float: left; width:100%;text-align:left;font-size:30px'> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-15-chapter-02-polymers-l-2_4-ux79wvhi84i-394-3667.2.jpg"></p> </div>