Plastic mold states of matter

1, the glass: ordinary plastic mold state above room temperature TG.

2, high elastic state: Temperature providers in TG, rubber-like polymer becomes soft and flexible.

3, the viscous flow state: James fluidizing temperature above the polymer plastic molds have appeared mobility and viscous fluid flow zone shift in plastic mold molding material viscous flow state into the lead.

Mobility:

Plastic mold under pressure at a certain temperature, can be sufficiently full performance of the various parts of the mold cavity, referred to as mobility.

Poor mobility, injection molding required greater pressure; liquidity very good, prone to cause salivation and parts overflow edge.

rheology: polymer under the action of the external flow and deformation properties called rheology.

Newtonian and non-Newtonian fluids.

Newtonian Fluid: depends (flow deformation) shear stress, shear rate and absolute viscosity, low molecular weight compound is a liquid or solution Newtonian fluid.

Most of the polymer melt during molding performance of non-Newtonian fluids.

crystalline: condensation can crystallize.

Amorphous and crystalline plastic molds plastic molds.

Crystalline types: nylon, polypropylene, polyethylene, amorphous plastic molds: ABS

heat-sensitive and water-sensitive.

phase melting: molten state, the two-phase melt together the plastic mold cannot be layered is, peeling.

stress cracking and melt fracture.