Thermosetting TMCD Polyester Clearcoat for Scratch Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thermosetting coating compositions face challenges in achieving a balance of improved tree resin resistance and scratch resistance, particularly due to the use of low molecular weight polymers to reduce VOC and increase coating solids, which adversely impacts scratch resistance.
Innovation Solution
A thermosetting coating composition comprising a polyester polyol made from 2,4,4-tetraalkylcyclobutane-1,3-diol (TACD) and an alicyclic diacid in specific ratios, combined with a crosslinker, to enhance tree resin resistance and scratch resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If low molecular weight polymers are used to reduce VOC and increase coating solids, then environmental compliance is improved, but scratch resistance deteriorates
Solution Approach 1:
The patent changes the chemical parameters of the polyester polyol by incorporating TACD with specific hydroxyl values (120-350 mg KOH/g) and specific monomer ratios (10-85 mol% TACD, 15-90 mol% other diols/polyols). This parameter optimization allows achieving both environmental compliance through reduced VOC and maintained scratch resistance through enhanced polymer chemistry
Solution Approach 2:
The patent creates a composite coating system by combining the TACD-based polyester polyol with specific crosslinkers (isocyanates, polyaminoamides, or polyesters with carboxyl groups) in controlled ratios. This composite approach synergistically improves both environmental performance and mechanical properties including scratch resistance
2Device complexity
If conventional polyester polyols are used, then formulation simplicity is maintained, but tree resin resistance is insufficient
Solution Approach 1:
The patent modifies the chemical parameters of the polyester polyol by incorporating TACD at 10-85 mol% with specific hydroxyl values (120-350 mg KOH/g). This parameter change significantly improves tree resin resistance while maintaining formulation simplicity through a single polyol component that integrates multiple functional benefits
Data Source
AI summary
This invention relates to aliphatic, carbamate-functional polyester resins for use in coatings. More particularly this invention relates to aliphatic, carbamate-functional polyester resins containing 2,2,4,4-tetramethyl-1,3-cyclobutanediol (TMCD) that exhibit improved scratch resistance and acid etch resistance when formulated into 2K automotive clearcoats. These carbamate-functional polyesters can be used as the sole resin in the clearcoat binder or in combination with other carbamate-functional acrylic resins and/or hydroxyl-functional acrylic and polyester resins.