Modified PTT Polyester Crystallization Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
PTT polyester fibers face issues with crystallization defects during spinning and processing, leading to chromatic differences, mechanical damage, and unrecoverable scratches due to their unique molecular structure and fast crystallization speed, which restricts their application and care.
Innovation Solution
A method is introduced to modify poly(1,3-propanediol terephthalate) by adding linear polyester and polyethylene glycol with specific molecular weights during the esterification and polymerization reactions to enhance crystallinity, stability, and softness, thereby improving the fiber's properties and reducing defects during spinning and processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If PTT polyester is spun at relatively low temperature to prevent melt degradation, then fiber quality and hand feel are improved, but crystallization is insufficient during winding and stretching, leading to chromatic differences and color bars
Solution Approach 1:
The patent modifies the polymerization parameters by adding linear polyester and polyethylene glycol to change the molecular structure and crystallization behavior of PTT, enabling sufficient crystallization at lower spinning temperatures while maintaining fiber quality
Solution Approach 2:
The patent creates a composite polymer system by incorporating linear polyester (0.5-6% by mass) and polyethylene glycol (0.5-8.5% by mass) into the PTT polymerization system, combining the properties of different polymers to achieve both low-temperature processability and sufficient crystallization
2Manufacturing precision
If PTT polyester crystallization speed is fast and crystallization degree is high, then fiber structure is well-formed, but minor variations in spinning conditions cause inner structure changes, bringing great difficulty to spinning process adjustment
Solution Approach 1:
The patent changes the crystallization kinetics parameters by adding linear polyester and polyethylene glycol, creating a more controlled and less sensitive crystallization process that maintains uniform fiber structure while being more tolerant to spinning condition variations
3Productivity
If PTT fiber is stretched by outer force during processing, then fabric is formed, but fiber recrystallizes under tension causing chromatic differences, color bars, and unrecoverable mechanical damage
Solution Approach 1:
The patent performs preliminary crystallization modification during polymerization by adding linear polyester and polyethylene glycol, pre-establishing a stable crystalline structure that prevents further recrystallization during subsequent stretching and processing operations
Solution Approach 2:
The patent creates a cushioning effect against recrystallization by incorporating linear polyester and polyethylene glycol that stabilize the molecular structure, preventing the harmful recrystallization process that would otherwise occur under tension during fabric processing
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The modification accelerates crystallization, improves dyeing stability, damage resistance, and softness of the fibers, eliminating chromatic differences and mechanical damage, and expands the application scope of PTT fibers in high-grade fabrics.
Implementation Method 1
PTT polyester possesses crystallization property similar to Nylon 6. Its crystallization speed during spinning is fast and crystallization degree is high.
Data Source
AI summary
A method is disclosed herein for the preparation of modified poly (1,3-propanediol terephthalate). The method comprises adding linear polyester with average molecular weight of 800˜3000 and polyethylene glycol with average molecular weight of 200˜2000 into polymerization monomers before polymerization reaction, wherein the linear polyester is a polymer obtained by reaction of C3 ˜C10 straight chain aliphatic dicarboxylic acid or 1,4-cyclohexane diformic acid with C2 ˜C10 straight chain aliphatic diol or 1,4-cyclohexane diformic acid; the linear polyester is 0.5%˜6% of the mass of polymerization monomers; the polyethylene glycol is 0.5%˜8.5% of the mass of polymerization monomers.