UHMWPE Powder Torque Control for Uniform Fiber Diameter
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The gel spinning method for producing ultra-high molecular weight polyethylene fibers faces challenges in achieving a uniform thread diameter, leading to difficulties in obtaining high-strength fibers with consistent properties.
Innovation Solution
A specific ultra-high molecular weight polyethylene powder with controlled viscosity-average molecular weight, torque measurement conditions, and additives is used to produce fibers with a uniform diameter and improved drawability, involving a mixture of 5 parts by mass of the powder and 95 parts by mass of liquid paraffin, kneaded under specific temperature and heating rate conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the gel spinning method is used to produce ultra-high molecular weight polyethylene fibers, then the fibers achieve very high strength and modulus of elasticity, but the thread diameter becomes non-uniform
Solution Approach 1:
The patent applies parameter changes by precisely controlling the viscosity-average molecular weight within 10×10^4 to 1000×10^4 and the torque difference (T80-T20) within 0.1°C to 50°C. These parameter specifications ensure the polyethylene powder has optimal flow and melting characteristics, enabling uniform thread diameter while maintaining high strength through controlled molecular weight distribution
Solution Approach 2:
The patent performs preliminary action by pre-processing the polyethylene powder to achieve specific physical and chemical properties before spinning. The powder is pre-characterized for viscosity-average molecular weight, torque values at different temperatures, and particle size distribution, ensuring it is ready for consistent gel spinning that produces uniform fibers with high strength
2Strength
If ultra-high molecular weight polyethylene powder with high molecular weight is used, then the fiber strength increases, but the drawability and continuous spinnability decrease
Solution Approach 1:
The patent resolves this contradiction through parameter changes by optimizing the viscosity-average molecular weight to a specific range (10×10^4 to 1000×10^4) and controlling the torque difference parameter. This balance allows the high molecular weight polymer to maintain strength while achieving sufficient melt flow and solubility for drawability and continuous spinning
Solution Approach 2:
The patent applies dynamics by considering the temperature-dependent behavior of the polyethylene powder. The torque measurement at different temperatures (20°C and 80°C above melting point) captures the dynamic rheological properties, ensuring the material transitions smoothly from solid to melt state for continuous processing while maintaining molecular integrity for strength
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 approach results in ultra-high molecular weight polyethylene fibers with a uniform thread diameter, enhanced drawability, and high strength, overcoming the limitations of the gel spinning method by ensuring consistent physical properties and extended spinnable time.
Implementation Method 1
the raw material is kneaded at 130° C. for 30 minutes and then further kneaded at 240° C. for 15 minutes
Implementation Method 2
a heating rate from 130° C. to 240° C. is set to 22° C./min
Data Source
AI summary
The present invention provides an ultra-high molecular weight polyethylene powder having a viscosity-average molecular weight of 10×104 or higher and 1000×104 or lower, wherein a difference between a temperature at which a torque value reaches 80% of the maximum torque value and a temperature at which the torque value reaches 20% of the maximum torque value is 0.1° C. or more and 50° C. or less in torque value measurement.