PA6 Resin Composition for Single-Layer Hollow Extrusion Molding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

There is a need for a polyamide resin composition that can produce single-layer hollow molded articles using polyamide 6 as a main component, while minimizing the use of polyamide 11 and polyamide 12, and achieving excellent extrusion moldability, flexibility, impact resistance, and durability, as existing technologies either rely on polyamide 12 or are limited to multi-layer structures.

Innovation Solution

A polyamide resin composition comprising polyamide 6, a polyolefin with a functional group, and a plasticizer, with specific ratios and properties, enabling the production of single-layer hollow molded articles through extrusion molding, utilizing a copolymer of ethylene and an α-olefin with functional groups from maleic anhydride or itaconic anhydride.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If polyamide 12 is used as the main material for hollow molded articles, then excellent flexibility and impact resistance are achieved, but supply stability deteriorates due to limited manufacturers and raw materials

Engineering Contradiction:
Improveflexibility and impact resistanceVSAvoidsupply stability
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The invention changes the chemical composition parameters by replacing polyamide 12 with polyamide 6 as the base resin and adding specific amounts of polyethylene and polypropylene. This parameter substitution maintains the flexibility and impact resistance properties while using widely available polyamide 6, thereby resolving the supply stability issue.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite resin composition by combining polyamide 6 with polyethylene and polypropylene in specific ratios. This composite approach achieves the desired mechanical properties (flexibility and impact resistance) that were previously only available from polyamide 12, while using materials with stable supply chains.

Inventive Principle:
Principle #40Composite materials

2Reliability

If polyamide 6 is used instead of polyamide 12, then supply stability improves, but extrusion moldability for hollow molded articles deteriorates

Engineering Contradiction:
Improvesupply stabilityVSAvoidextrusion moldability
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The invention modifies the composition parameters by adding polyethylene and polypropylene to polyamide 6. This compositional change improves the extrusion moldability and hollow molded article formation capabilities while maintaining supply stability, as polyethylene and polypropylene are well-established extrusion materials.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The composite resin system combines the structural properties of polyamide 6 with the processing advantages of polyethylene and polypropylene. This composite approach enables excellent extrusion moldability and hollow molded article production, overcoming the processing limitations of pure polyamide 6 while maintaining its supply stability advantages.

Inventive Principle:
Principle #40Composite materials

3Ease of manufacture

If a multi-layer structure is used to achieve good extrusion moldability, then manufacturing complexity increases

Engineering Contradiction:
Improveextrusion moldabilityVSAvoidstructure complexity
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The invention merges the functions of multiple layers into a single-layer structure by using a composite resin composition that inherently provides both structural integrity and processing ease. The polyamide 6/polyethylene/polypropylene blend achieves extrusion moldability and hollow molded article formation in a single layer, eliminating the need for multi-layer construction and reducing manufacturing complexity.

Inventive Principle:
Principle #5Merging (Combining)

Data Source

PatentUS20250304788A1Polyamide resin composition for single-layer hollow molded article
Publication Date: 2025.10.02 UBE CORPORATION

AI summary

Provided is a polyamide resin composition for a single-layer hollow molded body having polyamide 6 as the main component, substantially without using polyamide 11 and polyamide 12, wherein the properties are equivalent to those of a multilayered hollow molded body, the extrusion moldability of the hollow molded body is excellent, and the flexibility, impact resistance, and durability of the obtained molded body are excellent.The polyamide resin composition is a polyamide resin composition for extrusion molding to produce a single-layer hollow molded body, which contains polyamide 6 (a), a polyolefin (b) having a functional, and a plasticizer (c); the relative viscosity of the polyamide 6 (a), measured at 25° C. when I g of the polyamide 6 (a) is dissolved in 100 mL of 96% sulfuric acid in accordance with JIS K6920, is 3.0-4.5; 100 mass % of polyamide resin composition contains 60-90 mass % of the polyamide 6 (a), 3-25 mass % of the polyolefin (b) having a functional group, and 3-20 mass % of the plasticizer (c); and the polyolefin (b) having a functional group is a copolymer of ethylene and a C4 or higher α-olefin having a group derived from at least one selected from the group consisting of maleic anhydride and itaconio anhydride.