Polypropylene Resin Composition with Metal Salt for Strength Balance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional polypropylene resin compositions lack a balance between tensile strength and impact resistance, which is essential for various applications requiring both mechanical properties and durability.
Innovation Solution
A polypropylene resin composition comprising 51 to 99% propylene polymer and 1 to 49% ethylene polymer, combined with a metal salt represented by a specific formula, to enhance isotactic pentad fraction and melt flow rate, thereby improving tensile strength and impact resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If traditional polypropylene resin compositions are used, then manufacturing simplicity is maintained, but the balance between tensile strength and impact resistance is insufficient
Solution Approach 1:
The patent employs a composite resin composition comprising propylene polymer, ethylene polymer, and metal salt in specific proportions (51-99% propylene polymer, 1-49% ethylene polymer, and 0.001-0.5 part by weight metal salt per 100 parts resin composition). This composite approach combines materials with complementary properties to achieve both high tensile strength and impact resistance simultaneously, resolving the technical contradiction between strength balance and composition complexity.
Solution Approach 2:
The patent optimizes specific parameters including the density of ethylene polymer (0.85-0.93 g/cm³), the amount of metal salt (0.001-0.5 part by weight), and the compositional ratios of propylene to ethylene polymer. By precisely controlling these parameters, the invention achieves optimal balance between tensile strength and impact resistance without requiring overly complex formulation.
2Strength
If higher metal salt content is added to improve tensile strength, then mechanical properties are enhanced, but moldability deteriorates
Solution Approach 1:
The patent precisely controls the metal salt content within 0.001-0.5 part by weight per 100 parts resin composition and optimizes the ethylene polymer density parameter (0.85-0.93 g/cm³). This parameter optimization ensures sufficient tensile strength while maintaining moldability by preventing excessive crystallization that would occur with higher metal salt concentrations.
Solution Approach 2:
The metal salt is distributed uniformly throughout the resin composition at optimized concentrations, creating local nucleation sites that enhance tensile strength without causing localized aggregation that would impair moldability. The specific dosage range ensures beneficial local effects without harmful concentration effects.
Data Source
AI summary
A polypropylene resin composition comprising (a) 100 parts by weight of a resin composition, which contains 51 to 99% by weight of a propylene polymer and 1 to 49% by weight of an ethylene polymer having a density of 0.85 to 0.93 g/cm3, and (b) 0.001 to 0.5 part by weight of a metal salt defined by a specific chemical formula; and a process for producing such a polypropylene resin composition, comprising the steps of (1) mixing 1 to 100 parts by weight of the metal salt with 100 parts by weight of the propylene polymer and/or the ethylene polymer, thereby producing a master batch, and (2) mixing the master batch with a mixture containing the propylene polymer and the ethylene polymer.