Butene-1 Hexene Copolymer Composition for Pipe Melting-Strength Balance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Butene-1 polymers, while offering good pressure resistance, creep resistance, and impact strength, face challenges in maintaining optimal melting temperature and molecular weight distribution for applications like pipe manufacturing.
Innovation Solution
A butene-1/hexene-1 copolymer with specific hexene-1 comonomer content and melting temperature, combined with optional olefin comonomers, is produced using Ziegler-Natta catalysts and specific polymerization processes to achieve desired mechanical properties and molecular characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If butene-1 polymer is used to achieve good pressure resistance and creep resistance, then the mechanical strength is improved, but the melting temperature control becomes difficult
Solution Approach 1:
The patent applies parameter changes by precisely controlling the hexene-1 comonomer content (2-4 wt%) and the melting temperature (≥115°C) to achieve the desired balance between pressure resistance and melting temperature. This involves adjusting polymerization conditions and catalyst systems to obtain copolymers with specific molecular weight distribution and comonomer incorporation, thereby resolving the contradiction between mechanical strength and melting temperature control.
2Strength
If butene-1 polymer is used to achieve good impact strength, then the toughness is improved, but the molecular weight distribution optimization becomes challenging
Solution Approach 1:
The patent utilizes parameter changes by optimizing the polymerization process parameters including catalyst type, temperature, pressure, and monomer feed rate to achieve a specific molecular weight distribution that maintains broad distribution for impact strength while controlling the average molecular weight. The use of Ziegler-Natta catalysts with specific modifiers enables precise control over these parameters.
3Temperature
If hexene-1 comonomer is added to butene-1 polymer, then the melting temperature is enhanced, but the comonomer content control becomes critical
Solution Approach 1:
The patent applies parameter changes by establishing a precise comonomer content range (2-4 wt% hexene-1) and corresponding melting temperature threshold (≥115°C) that must be simultaneously achieved. This requires careful control of hexene-1 feed rate, polymerization temperature, and catalyst activity to maintain the narrow window of acceptable comonomer incorporation while ensuring the melting temperature requirement is met.
Solution Approach 2:
The patent employs feedback control mechanisms where the comonomer content and melting temperature are monitored during polymerization, and the process parameters are adjusted in real-time to maintain the specified ranges. This includes measuring the molecular weight distribution and comonomer incorporation periodically and modifying the polymerization conditions accordingly to achieve the target properties.
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 copolymer exhibits enhanced melting temperature, mechanical strength, and molecular weight distribution, making it suitable for high-performance pipes with improved pressure resistance, impact strength, and creep resistance.
Implementation Method 1
produced using Ziegler-Natta catalysts and specific polymerization processes
Data Source
AI summary
A copolymer of butene-1 with hexene-1 having:1) a content of hexene-1 comonomer units from 2 to 4% by weight, based upon the total weight of the copolymer; and2) a melting temperature TmI equal to or higher than 115° C.