Polymers ME 250:Design Manufacturing I School of Mechanical Engineering Shanghai Jiao Tong University 1
Shanghai Jiao Tong University 1 Polymers ME 250: Design & Manufacturing I School of Mechanical Engineering
Outline Introduction ■Polymer(聚合体)Processing Summary Shanghai Jiao Tong University 2
Shanghai Jiao Tong University 2 Outline n Introduction n Polymer（聚合体） Processing n Summary
Introduction ■Learning Objectives Polymers as Engineering Materials Chemical Structure of Polymers a Commonly Employed Polymer Processing Techniques ■Applications Polymer Composites Shanghai Jiao Tong University 3
Shanghai Jiao Tong University 3 Introduction n Learning Objectives n Polymers as Engineering Materials n Chemical Structure of Polymers n Commonly Employed Polymer n Processing Techniques n Applications n Polymer Composites
Polymers Thermoplastics vs Thermosets Thermoplastics(热塑形塑料)-Plastics that can be repeated softened by heating and repeatedly hardened by cooling through a temperature range that is characteristic of the plastic.In the softened state,the plastic can be shaped into articles. Thermosets(热固性塑料)-Plastics which,after having been cured by heat or other means are mostly infusible or insoluble. Thermosets cannot be reprocessed. Shanghai Jiao Tong University 4
Shanghai Jiao Tong University 4 Polymers - Thermoplastics vs Thermosets Thermoplastics（热塑形塑料） – Plastics that can be repeated softened by heating and repeatedly hardened by cooling through a temperature range that is characteristic of the plastic. In the softened state, the plastic can be shaped into articles. Thermosets （热固性塑料）– Plastics which, after having been cured by heat or other means are mostly infusible or insoluble. Thermosets cannot be reprocessed
Polymers Thermoplastics vs Thermosets Thermoplastics molecules are linear or branched,and as a rule are soluble in specific organic solvents. In thermosets,the molecules are chemically cross-linked,and cannot be dissolved by organic solvents Thermosets Thermeplastics Three-dimeasional amorphous cross-linked Filament molecules molecules amorphous partially crystelline Shanghai Jiao Tong University 5
Shanghai Jiao Tong University 5 Polymers - Thermoplastics vs Thermosets Thermoplastics molecules are linear or branched, and as a rule are soluble in specific organic solvents. In thermosets, the molecules are chemically cross-linked, and cannot be dissolved by organic solvents