The final reaction and shape of the end product happens in the mould. For more details and other topics, please log on to CoolGyan website and download app. Polymers Class 12 Chemistry MCQs Pdf. A natural resinous polymer called lignin has a cross-linked structure similar to bakelite. On the other hand, LDPE has lots of side chains. Epoxy Resin: These are a class of polymers which contain epoxide groups. So, this completes our topic on Thermosetting Polymers or Thermosetting Plastics or Thermosets. These polymers are also referred to as Thermosets or Thermosetting Plastics. The image on the left shows a filament wound container. Tips for Teachers: Helping Students Struggling with Online Learning. The second component is a cross-linker or comonomer which acts as a cross-linking substance. Your email address will not be published. Thermosetting polymers have a cross-linked 3D structure. Further information on how polymers. To learn more, visit our Earning Credit Page. The density of thermoset is dependent on constituent components used to create the polymer. Thermosetting polymers or thermosets are prepared by a chemical reaction of at least two or more materials. This reflects the fact that above Tg they may be shaped or pressed into molds, spun or cast from melts or dissolved in suitable solvents for later fashioning. Thermosetting and thermoplastics are two different classes of polymers, which are differentiated based on their behavior in the presence of heat.The main difference between thermoplastic and thermosetting plastic is, thermoplastic materials have low melting points; therefore, they can be remoulded or … These are used to produce construction equipment panels. Polyethylene is an example of a thermosoftening polymer. One of the reactants is a monomer which forms the final chain of polymer. The initial display is of Bakelite, one of the first completely synthetic plastics to see commercial use (circa 1910). These polymers which are in the soft solid or viscous state on heating undergo extensive cross-linking in moulds and become irreversibly hard as well as insoluble products. Another example is Melamine which has a capacity to resist fire and heat much efficiently than other plastics. How Hard is the CSET Multiple Subjects Test? The Haber Process: Commercial Uses & Chemistry… 's' : ''}}. Visit BYJUS to learn more about it. You can test out of the However, thermoset plastics are brittle and tend to char and burn if heat is applied for a prolonged state. Most of the polymers described above are classified as thermoplastic. Bakelite: Bakelite is phenol formaldehyde resin with monomer chemical formula of. Another group of polymers, characterized by a high degree of cross-linking, resist deformation and solution once their final morphology is achieved. Chemistry MCQs for Class 12 Chapter Wise with Answers PDF Download was Prepared Based on Latest Exam Pattern. Laura has a Masters of Science in Food Science and Human Nutrition and has taught college Science. Services. Bakelite: Bakelite is phenol formaldehyde resin with monomer chemical formula of, -O). Thermosetting polymers are polymers that keep their shape once they have been set. Urea-Formaldehyde: As the name suggests, it is produced from urea and formaldehyde, and is used to make adhesives, boards and other moulded products. We hope you enjoyed learning about it. There are a variety of ways in which these can be moulded, some being: Reaction Injection Moulding (RIM): The two components required to make a thermoset are initially put into two separate tanks from which they are pressure fed into a mix-head.