Aromatic Liquid Crystal Polyester Terminal Group Control

The patent changes the chemical composition parameters of the liquid crystalline polyester by incorporating specific terminal groups (carboxyl, hydroxyl, and acetyl groups in controlled ratios) and hydroquinone-derived structural units (2-15 mole percent). This compositional parameter adjustment enables the polymer to achieve both thermal stability and improved metal adhesion property simultaneously, resolving the contradiction between these two properties.

The patent converts the harmful gas evolution problem into a beneficial solution by carefully selecting terminal group compositions. The controlled presence of carboxyl, hydroxyl, and acetyl groups in specific ratios minimizes acetic acid vapor evolution during heating while maintaining thermal dimension accuracy. This transforms the harmful fogging effect into a controlled process with reduced harmful emissions.

The patent creates a composite molecular structure within the liquid crystalline polyester by combining multiple functional units: hydroquinone-derived structural units (2-15 mole percent), terminal carboxyl groups, terminal hydroxyl groups, and terminal acetyl groups in controlled ratios. This composite structure integrates multiple functions into a single material system, simultaneously achieving basic thermal properties along with improved fog resistance, metal adhesion property, and creep resistance.

The patent applies local quality by creating specific terminal group distributions at the molecular level. Rather than uniform composition throughout, the invention places specific functional groups (carboxyl, hydroxyl, acetyl) at terminal positions with controlled ratios. This localized functional group arrangement at the chain ends provides enhanced metal adhesion property and fog resistance while maintaining overall thermal stability of the bulk material.