Show clearly each stage of your calculations and working You

Show clearly each stage of your calculations and working. Your answer should be no more than about 400 words long b. Briefly explain how the atomic bonding in polymers and ceramics greatly influences the differences in their mechanical properties and why these materials cannot be strengthened in the same way as metals.

Solution

The polymer is composed of large no of repeating units(small molecules) called manomers.The monomers are joined together end to end in a polymerization reaction.The unique charecteristics of a polymer is that a molecule is either a long chain or a network of repeating units all covalently bonded together.In some cases these are also bonded by secondary bonds such as van der waals or hydrogen bonds which are very weak in nature and can be esaily broken with the application of heat.These are generally non crystaalline solids at room temperature.Ploymers are also connected together often by relatively short cross links between monomers.The mechanical properties of polymers is markedly influenced by molecular structure and it is therefore very much structure sensitive.Due to presence of covalent bonds and secondary bonds also in many cases crosslinking ,polymers have low strength ,poor dimensional stability,are unsuitable for high temperature application ,and are comparitively less brittle than ceramics.

As in case of ceramics,they are inorganic,non metallic materials that consists of metallic and non metallic elements bonded together primarily by ionic bond or in some cases and/or covalent bonds.The percentage of ionic and covalent charecter for the bonds between the atoms can be obtained by knowing the electro negativity of different atoms.Ionic bonds give ceramics relatively high stability than polymers.They also have higher meltung point than polymers and metals.There covalent charecter gives them high hardness,high melting and low electrical conductivity at room temperature.

THESE materials i.e ploymers and ceramics cannot be strenghtened in the same way as metals because of the different types of bonding present in these materials.

Metals are bonded by ionic bonds and are generally strenghtened by diffusion as they have a fixed crystal lattice system,there always remain a chance of interstitiality or substitutionality.

The crystal structure of ceramic is however more complex as compared to metals,SINCE ATOMS OF DIFFERENT SIZE AND ELECTRONIC CONFIGURATION ARE ASSEMBELED TOGETHER.

Ploymers behave differently to metals as there is no ionic bond present and presence of covalent and secondary bonds make it impossible to strenghten it in the same way as metals.In polymers strengthening is done by crystallization,cross-linking,chain stiffening and also by adding filler materials.