Crosslinked Polyolefin Pipe Composition for Low-Leaching Water Use
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing polyolefin pipes used in water applications face challenges with additive leaching, which can contaminate fluids and fail to meet standards for total organic carbon (TOC), taste, and odor, requiring additional post-extrusion treatments.
Innovation Solution
The use of a polymeric pipe formed with a polyolefin structural polymer and a bismaleimido crosslinker, specifically a compound of formula (I) with R as a C2-C24 alkyl, in amounts of 0.02 to 5% by weight, which reduces leaching and eliminates the need for additional post-extrusion treatments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If conventional polyolefin pipes are used with standard additives and crosslinking agents, then the pipes achieve adequate structural properties and crosslinking, but chemical residues leach into water causing TOC, taste, and odor issues
Solution Approach 1:
The patent changes the chemical parameters by using a bismaleimido crosslinker instead of conventional peroxide or silane crosslinking agents. This substitution fundamentally alters the crosslinking chemistry to produce minimal leaching, thereby resolving the contradiction between structural integrity and water quality compliance.
Solution Approach 2:
The patent employs a crosslinking system where the crosslinker fully reacts and becomes part of the permanent polymer network, eliminating the need for residual catalysts or unreacted additives that would otherwise leach. This approach treats the crosslinking agents as consumable materials that are completely utilized rather than persistent residues.
2Object-affected harmful factors
If additional post-extrusion treatments are applied to reduce leaching, then water quality standards are met, but manufacturing complexity and processing time increase
Solution Approach 1:
The patent performs preliminary action by selecting a bismaleimido crosslinker that inherently minimizes leaching from the outset, rather than requiring subsequent treatment steps. The crosslinking chemistry is designed upfront to produce a stable, low-leaching product, eliminating the need for post-extrusion remediation processes.
Solution Approach 2:
The patent extracts the problem of leaching at its source by removing conventional crosslinking agents and additives that cause contamination. By using bismaleimido crosslinkers that fully integrate into the polymer matrix without residual leaching, the harmful components are effectively taken out of the system.
3Strength
If conventional crosslinking agents are used to achieve high crosslinking density, then structural integrity is improved, but leaching of chemical residues increases
Solution Approach 1:
The patent changes the chemical nature of the crosslinking agent from peroxide or silane-based systems to bismaleimido crosslinkers. This parameter change maintains high crosslinking density while fundamentally altering the reaction products to be non-leaching, thereby resolving the contradiction between strength and residue generation.
Solution Approach 2:
The patent creates a composite crosslinked structure where the bismaleimido crosslinker forms integral part of the polymer network. The crosslinked polyolefin composition represents a composite material system where the crosslinking agents and polymer matrix are chemically integrated, eliminating separate residue phases that would leach.
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 solution effectively minimizes chemical residue leaching, meeting or exceeding standards for TOC, taste, and odor without additional processing steps, enhancing the pipes' structural integrity and resistance to aging.
Implementation Method 1
the crosslinking is induced by peroxide under the influence of heat and high pressure... The resultant PEX-a composition is crosslinked through carbon-carbon bonds to form the cross-linked polymer network
Implementation Method 2
The primary reaction is the formation of free radicals upon decomposition of the peroxide
Implementation Method 3
the free radical abstracts hydrogens from the PE polymer chains. The latter gives new carbon radicals, which next combines with neighboring PE chains to form stable carbon-carbon bonds
Implementation Method 4
the crosslinking occurs in a secondary post-extrusion process that is accelerated by a combination of heat and moisture. The latter combination is the active 'reagent', which is involved in the primary hydrolysis and condensation reaction
Implementation Method 5
the crosslinking occurs in a secondary post-extrusion process that is accelerated by a combination of heat and moisture. The latter combination is the active 'reagent', which is involved in the primary hydrolysis and condensation reaction
Implementation Method 6
In the PEX-c process, no chemicals are needed in order to facilitate the crosslinking process, but instead high energy electron beam (EB) irradiation is utilized to create the free radicals necessary for the hydrogen abstraction and subsequent crosslinking to take place
Data Source
AI summary
This invention relates to a polymeric pipe, and more particularly a polymeric pipe where the pipe comprises a crosslinked polyolefin formed from extruded polyolefin comprising a bismaleimido crosslinker. This invention relates to the manufacturing of plastic pipes and tubing of polyolefinic polymers such as polyethylene, with crosslinking by a bismaleimido crosslinker, to produce crosslinked polyethylene (PEX) pipes and tubing.