The document discusses applications of a thermoformability analyzer to quantify and compare the thermoformability of plastic materials. It outlines key factors that affect thermoformability like material properties, processing parameters, and part design. Current test methods are described as inconsistent and not reflective of actual thermoforming conditions. The thermoformability analyzer aims to address these issues by simulating the full thermoforming process including heating, stretching in 3D, forming, and cooling, under controlled and repeatable conditions. Results from the analyzer can help processors optimize materials and processing parameters for thermoforming. A thermoformability index is proposed as a standardized metric to compare materials.
7. Test Methods Inconsistent results, grip extrusion, annealing Hot tensile test Repeatable, effect of temperature DMTA Repeatable, correlates with Sag test, expensive equipment Stress Relaxation No external force, geometry dependent, measure of only melt strength Sag test > Tm, cooling effect, uni-directional, not applicable to all materials Melt Tension Easy, measure of only MW MFR Major Short coming Test Method
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12. Variables Shrinkage Extrusion, storage Additive package impurity % of fillers Forming speed % regrind Type of fillers Plug temperature Volatiles Rho, k, Cp Plug material Color η o , η el Plug geometry Layers % LCB, % Xl Part geometry Residual stresses Tg, Tm, % Xc Forming Method Thickness Molecular Structure Process Feed Stock Material
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14. Output Range Input Temp. vs. Time Plug assist, Vacuum Method Force vs. Time Any type Resin Type Test Input – Output Variable Plug Dwell time 10- 180 mm/second Forming Speed Variable Cooling Time 100 lb Maximum Force 23 C to 120 C Plug temperature Force vs. Depth Epoxy, Polished Aluminum Plug Material Force at Max Draw Depth Variable Heat Soak time Draw vs. time 60 C to 280 C Forming Temperature Force vs. Draw Depth 10 mil to 375 mil Sheet Thickness