materials and their properties

• ceramics have high melting points
• composites are generally made of two different materials that are embedded in eachother that are generally strong
• low density poly(ethene) is made at a moderate temperature under high pressure. it is flexible
• high density poly(ethene) is made at a lower temperature and pressure with a catalyst. it is more rigid
• thermosetting polymers contain monomers that can form cross links between the polymer chains holding them together in a solid structure. they are strong, hard and rigid
• thermosoftening polymers contain individual polymer chains entwined together with weak forces between. you can melt and remould them
• polymers and ceramics are insulators of heat and electricity