Piezoelectric Cavity Core Adjustment for Micro Resonator Frequency Stabilization
Dynamic piezo core adjustments during moulding freeze sub-micron resonator dimensions, stabilizing frequency and eliminating post-moulding laser trim steps.
LCP Molecular Orientation
Meaning
Liquid crystal polymer molecular orientation describes the alignment of rigid polymer chains along the primary shear axis during thermoplastic processing. High directional order develops under the strong extensional flow fields typical of thin wall injection moulding and high speed extrusion. Structural anisotropy governs mechanical properties by producing exceptionally high tensile strength and thermal resistance in the parallel direction while leaving transverse planes vulnerable to splitting.
That structural alignment occurs during the cooling phase when the shearing forces of the molten front lock the rigid mesogens into a fixed parallel arrangement. Moulders must control melt temperature and injection velocity tightly because excessive relaxation destroys the desired chain alignment before solidification finishes.
Shear Rate
High fluid velocity inside narrow gate geometries generates the necessary frictional forces to align rigid polymer domains effectively. Shear stress within the runner system forces the flat aromatic backbones into parallel planes before the material enters the mold cavity. Low injection speeds fail to develop sufficient extensional flow, leaving the molded part with random domain dispersion and inadequate mechanical strength.
Crystallinity Gradient
Rapid freezing near the chilled tool steel surface locks the molecular chains into a skin layer possessing extreme orientation and minimal transverse ductility. Slower cooling rates in the core allow molecular relaxation to occur, producing a thicker internal region with randomized chains and lower mechanical performance. Variations in wall thickness alter this skin to core ratio, changing the bulk stiffness and thermal distortion temperature of the finished component.
Thermal Deflection
Internal stress resulting from frozen chain alignment causes severe warpage when the finished part experiences temperatures approaching the softening point of the resin. Virgin material maintains predictable dimensional stability because the molecular weight distribution supports uniform chain packing across the entire shot volume. Contaminated regrind introduces foreign viscosity profiles that disrupt the local shear history and trigger unpredictable shrinkage variations along the molded length.