Butene Polymer Composition for Creep Resistance and Uniform Deformation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional poly-1-butene resin compositions excel in tensile creep characteristics but are poor in stretchability and processability, necessitating an improvement in uniform deformability.

Innovation Solution

A butene-based polymer composition comprising 96.0 to 99.5 parts by mass of a butene-based polymer and 0.5 to 4.0 parts by mass of a propylene/ethylene/α-olefin random copolymer, ensuring a positive primary differential value of stress in a strain range of 1.0 or less in a stress-strain curve, enhancing tensile creep characteristics and uniform deformability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional poly-1-butene resin compositions are used, then tensile creep characteristics are excellent, but stretchability and uniform deformability are poor

Engineering Contradiction:
Improvetensile creep characteristicsVSAvoidstretchability and uniform deformability
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The invention changes the compositional parameters by introducing a specific copolymer component (propylene/ethylene/α-olefin random copolymer) with controlled composition ratios and molecular weight distribution, while maintaining the base poly-1-butene content within a specific range. This parameter adjustment resolves the contradiction by achieving both excellent tensile creep resistance and improved uniform deformability without yield points

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite resin system combining poly-1-butene homopolymer or copolymer with propylene/ethylene/α-olefin random copolymer in specific proportions. This composite structure integrates the high creep resistance of poly-1-butene with the enhanced deformability provided by the copolymer component, eliminating the trade-off between the two properties

Inventive Principle:
Principle #40Composite materials

2Reliability

If the composition is optimized for tensile creep resistance, then creep characteristics improve, but processability deteriorates

Engineering Contradiction:
Improvetensile creep characteristicsVSAvoidprocessability
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The invention optimizes processability by controlling the molecular weight distribution (Mw/Mn ≤ 4.0) of the copolymer component and adjusting its content within 5-50 parts by mass per 100 parts of poly-1-butene. These parameter changes reduce processing resistance while maintaining the tensile creep resistance provided by the poly-1-butene base resin

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention applies local quality by having different components serve different functions: the poly-1-butene provides bulk creep resistance while the copolymer component locally enhances deformability and processability. This functional differentiation allows the material to exhibit both high reliability and good processability in different operational contexts

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3770212B1Butene-based polymer composition
Publication Date: 2023.09.13 MITSUI CHEMICALS INC

AI summary

[Object] To provide a butene-based polymer composition excellent in tensile creep characteristics and uniform deformability in a balanced manner. [Solution] A butene-based polymer composition including 94.5 to 99.5 parts by mass of a butene-based polymer (A) including 70 to 100 mol % of a constituent unit derived from 1-butene, and 0 to 30 mol % of a constituent unit derived from an α-olefin having 2 to 10 carbon atoms, and having an MFR of 0.01 to 50 g/10 min; and 0.5 to 5.5 parts by mass of a propylene/ethylene/α-olefin random copolymer (B) including 45 to 89 mol % of a constituent unit derived from propylene, 1 to 25 mol % of a constituent unit derived from ethylene, and optionally 0 to 30 mol % of a constituent unit derived from an α-olefin having 4 to 20 carbon atoms, wherein a primary differential value of stress (d (stress)/d (strain)) is always a positive value in a strain range of 1.0 or less in a stress-strain curve obtained by performing a predetermined tensile test.