Organic Chemistry Module 8 Portage 219 Exam Questions With 100% Verified Solutions

Organic Chemistry Module 8 Portage 219 Exam Questions With 100% Verified Solutions the final polymer retains all of the atoms of the monomer - ANSWER The defining characteristic of chain-growth polymers step growth polymerization - ANSWER formed by the reaction between 2 different functional groups on different monomer molecules with the accompanying loss of some small molecule (typically water) The final polymer chain does NOT include all the atoms initially present in the monomer molecules - ANSWER The defining characteristic of step-growth polymers condensation polymers - ANSWER step-growth polymers also known as: typically di or polyfunctional - ANSWER functionality of step-growth monomers alternating order in the final polymer chain - ANSWER appearance of monomers in step-growth polymerization by carbon-heteroatom bond formation - ANSWER how step-growth polymers generally grow carbon-carbon bond formation - ANSWER how chain-growth polymers generally grow Polyamide (Nylon) - ANSWER formed by combining 1,6-diaminohexane (amine) with 1,6-hexandioic acid (carboxylic acid) amine functionality reacts with carboxylic acid functionality to form an amide with a corresponding loss of a water molecule cellulose, polypetide chains, beta-Hydroxybutyric acid - ANSWER naturally occurring step-growth/ condensation polymer examples Lexan - ANSWER step-growth polymer: polycarbonate eye glasses, auto parts, drinking glasses Kevlar - ANSWER step-growth polymer: polyamide body armor, tires, helmets Dacron, Mylar - ANSWER step-growth polymer: polyester eletric/thermal insulation, helium balloons, artificial limbs 1. free radical 2. cationic 3. anionic - ANSWER three main mechanisms for addition/ chain-growth polymerization begins by creating a reactive intermediate that starts the chain reaction - ANSWER For all three main addition mechanisms, how does polymerization begin? free-radical addition polymerization - ANSWER a monomer reacts with a free-radical initiator to create a free-radical free-radical - ANSWER an atom or a group of atoms that has one unpaired electron radical initiator - ANSWER a reagent that creates radicals, has relatively weak covalent bonds which can be homolyzed 1. electrically neutral 2. quite reactive and reacts quickly to pair up the lone electron 3. formed from radical initiators - ANSWER 3 main characteristics of free-radicals Homolyzed - ANSWER broken so that each atom joined by the bond gets one of the two electrons in the bond benzoyl peroxide - ANSWER example of a radical initiator (o-o bond = weak and can undergo homolysis upon heat or UV exposure to produce 2 benzoyl radicals) only a small amount of radical initiator is needed compared to the concentration of monomers present -some remains in final product but it does not affect the product - ANSWER how much initiator is needed in polymerization and does any remain at the end of the reactions? 1. the monomer used 2. the molecular weight of the final polymer chain - ANSWER two main things that control polymer properties radical can attack + homolyze C=C of monomer to create a reactive intermediate that starts polymerization - ANSWER what happens after the radical initiator has formed radicals? adds to the LEAST substituted carbon of the C=C bond because this carbon is easier to approach and less hindered to produce a more stable radical intermediate - ANSWER which substituent does the radical add to in the monomer?