PHYSICS 102 Lecture Notes - Butane, Rede Ferroviária Nacional, Crystallinity
Document Summary
Structure of polymers: hydrocarbons are often long structures consisting of h and c molecules, joined by covalent bonds. Alkanes: methane, ethane, propane and butane, for example, singles bonds (cn h2n+2), saturated, cannot undergo polymerisation. Alkenes: ethene, propene and butane methene does cannot exist, double bonds (cn h2n), unsaturated, can undergo polymerisation. Monomers and polymers: a process known as additional polymerisation" is used to form a chain of generally identical monomers. Condensation polymerisation: two different monomers bonding to create a new" polymer. Polymer materials: a diverse group of engineering materials, main components include adhesives, paints, plastics, resins and rubbers. Classification of polymers: thermoplastics exhibit plastic flow at elevated temperatures, recyclable; relatively weak, thermosets temperature, or a catalyst, causes a permanent reaction to occur, non-recyclable; higher performers, also available as a powder. In theory, the longer the chains, the stronger the material. Cross-linking: tougher and less flexible, which means they cannot be easily stretched, with higher melting points.
