make video on it---Course Contents: Introduction: Define polymer, monomer, repeating unit, polymerization with example, Degree of polymerization, end group etc. Classify Polymers based on the origin, Chemical structure, polymer mechanism, thermal behavior and und uses. Chain polymerization: Define initiator, free radicals, inhibitors with suitable illustration, Classification of polymerization, Definition and Mechanism of Free radical, Ionic and Co-ordination polymerization, Kinetics of chain polymerization. Step polymerization: Definition and Mechanism of polycondensation, polyaddition and ring-opening polymerization, kinetics of step polymerization, techniques of polymerization (liquid, gas and solid phase). Page 49 of 147 Molecular Weight and molecular weight distribution: Average molecular weight-Number average molecular weight, weight average molecular weight, Viscosity average molecular weight and their measurements, molecular weight distribution/ polydispersity, effect of molecular weight on polymer properties. Properties, application and uses of Polymer: Properties of polymer (Mechanical, Thermal, Chemical, Electrical, Degradability etc.) Uses of polymers in everyday life, Name of polymers and their specific uses, advantages of polymers over other materials. Glass Transition Temperature: Definition of Glass Transition Temperature (Tg), Melting temperature (Tm), Flow Temperature (Tf) etc. Transition and associated properties of polymer, Factors influencing the glass transition temperature, Importance of glass transition temperature, Heat distortion temperature. Crystallinity in polymer: Crystalline solid and their behavior towards X-rays, Degree of crystallinity, crystallisability, polymer crystallization, structural regularity and crystallisability, crystallinity and their effect on different properties of polymers. Polymer degradation: Define polymer degradation, Types of polymer degradation, Thermal and Mechanical Degradation, Ultrasonic and Photo degradation, Oxidative and hydrolytic degradation.

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Welcome to our introduction to polymers. A polymer is a large molecule made up of many repeating units called monomers. The process of combining monomers to form polymers is called polymerization. For example, ethylene monomers can polymerize to form polyethylene. The degree of polymerization refers to the number of repeating units in the polymer chain. Polymers can be classified based on their origin, chemical structure, polymerization mechanism, and thermal behavior. Chain polymerization involves three key steps. First, initiation occurs when an initiator creates free radicals - highly reactive species with unpaired electrons. These radicals then attack monomers in the propagation step, creating growing polymer chains. Finally, termination happens when two radical chains combine to form the final polymer. There are three main types: free radical polymerization, ionic polymerization, and coordination polymerization. Inhibitors can stop this process by consuming the active radicals. Polymers are large molecules composed of repeating structural units called monomers. The process of combining monomers to form polymers is called polymerization. Key concepts include the degree of polymerization, which indicates how many monomer units are in the polymer chain. Polymers can be classified by origin as natural, synthetic, or semi-synthetic materials. Chain polymerization is initiated by reactive species like free radicals. An initiator starts the reaction by forming radicals with unpaired electrons. These radicals react with monomers to form growing polymer chains. The polymerization rate depends on monomer and radical concentrations. Inhibitors can prevent polymerization by reacting with radicals. Different mechanisms include free radical, ionic, and coordination polymerization. Step polymerization involves different mechanisms. In polycondensation, monomers react with elimination of small molecules like water or hydrogen chloride, forming polymers like polyesters. Polyaddition occurs when monomers react without eliminating by-products, such as in polyurethane formation. Ring-opening polymerization involves cyclic monomers that open to form linear polymer chains. These processes can occur in liquid, gas, or solid phases, each offering different advantages for specific applications. Molecular weight is crucial for polymer properties. Number average molecular weight considers the number of molecules, while weight average considers their mass contribution. The polydispersity index indicates the distribution breadth. Higher molecular weights generally improve mechanical strength and thermal stability but can make processing more difficult. Glass transition and melting temperatures are key thermal properties that depend on molecular structure and weight. Polymer degradation is the breakdown of polymer chains due to various external factors. Thermal degradation occurs due to heat, mechanical degradation from stress and strain, and photo-degradation from UV radiation. Oxidative degradation involves reaction with oxygen, while hydrolytic degradation occurs in the presence of water. Ultrasonic degradation results from high-frequency sound waves. These processes lead to reduced molecular weight, loss of mechanical properties, color changes, and brittle behavior in polymers. Molecular weight significantly affects polymer properties. Number average molecular weight considers the number of molecules, while weight average considers mass contribution. The polydispersity index measures distribution breadth. Higher molecular weights generally improve mechanical strength and thermal stability but make processing more difficult. Key thermal properties include glass transition temperature where polymers become flexible, and melting temperature for crystalline regions. Understanding these relationships is crucial for polymer design and application. Polymers have diverse applications from packaging materials like polyethylene bottles to high-performance textiles and electronic components. Their advantages include being lightweight, corrosion-resistant, and cost-effective. However, polymers can degrade through thermal, photo, oxidative, hydrolytic, and mechanical processes, breaking polymer chains into smaller fragments. The glass transition temperature marks where polymers change from rigid to flexible behavior. Crystallinity, the ordered arrangement of polymer chains, significantly affects mechanical and thermal properties, with crystalline regions providing strength and amorphous regions providing flexibility.