Polycarbonate Resin Composition for Thin Films

The patent adjusts the viscosity average molecular weight of the polycarbonate resin to a specific range (28,000 to 60,000) to optimize the balance between mechanical strength and flowability. This parameter change allows the resin to maintain adequate flow characteristics for extrusion molding while providing sufficient mechanical strength when combined with inorganic fillers.

The patent creates a composite resin composition by combining polycarbonate resin with specific inorganic fillers (such as glass fibers, talc, or calcium carbonate) and flame retardants. This composite approach enhances mechanical strength while the carefully selected composition maintains workability for thin-walled extrusion molding.

The patent specifies a precise viscosity average molecular weight range (28,000 to 60,000) for the polycarbonate resin to counterbalance the heat resistance reduction caused by flame retardant addition. This parameter optimization ensures that the resin maintains adequate heat resistance while achieving V-0 or V-1 flame retardance ratings in thin-walled products.

The patent applies flame retardants locally within the resin matrix at controlled concentrations (typically 5-30 wt%), creating zones of flame retardancy without uniformly compromising the overall heat resistance of the material. This localized approach allows thin-walled products to achieve excellent flame retardance while maintaining sufficient heat resistance for electrical and electronic applications.

The patent optimizes the viscosity average molecular weight of the polycarbonate resin to a higher range (28,000 to 60,000) compared to conventional resins. This parameter change enhances the resin's inherent flame retardance and mechanical properties, allowing thin-walled extrusions (0.8 mm or less) to achieve V-0 or V-1 UL94 ratings without requiring excessive filler loading that would compromise flowability.

The patent develops a specialized composite formulation combining polycarbonate resin with inorganic fillers and flame retardants in optimized proportions. This composite structure provides enhanced flame retardance and mechanical strength at reduced thickness, enabling miniaturized electrical and electronic equipment housings to meet safety standards while maintaining structural integrity.

The patent adjusts the viscosity average molecular weight to a specific range (28,000 to 60,000) that provides optimal balance between mechanical properties and melt flow characteristics. This parameter optimization enables the resin composition to be successfully extruded into large-area thin-walled products while maintaining adequate mechanical strength and dimensional stability.

The patent uses specific inorganic fillers with controlled particle size distributions and aspect ratios to enhance mechanical properties locally within the resin matrix without excessively compromising overall flowability. This selective approach allows large-area extrusion molding of thin-walled products while maintaining sufficient mechanical strength.