Polyfunctional Alcohol-Modified Chlorinated Carboxylated Polyolefins Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing adhesion-promoting primer compositions for polyolefin surfaces face challenges with solubility in typical solvents and adhesion performance, especially under exposure to humidity and gasoline, with high chlorine content leading to poor adhesion and water resistance.
Innovation Solution
Polyfunctional alcohol-modified chlorinated carboxylated polyolefins are prepared by reacting polyolefins with unsaturated carboxylic esters, acids, anhydrides, or vinyl monomers, followed by chlorination and further modification with polyfunctional alcohols, enhancing solubility in coating solvents without compromising adhesion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the chlorine content of chlorinated polyolefins is increased to improve solubility in various solvents, then solubility is improved, but adhesion performance deteriorates, especially after exposure to humidity and gasoline
Solution Approach 1:
The patent changes the chemical parameters of the polyolefin by introducing carboxyl groups through reaction with unsaturated carboxylic acids, anhydrides, or esters. This chemical modification allows the polymer to achieve good solubility in typical coating solvents without requiring high chlorine content, thereby maintaining adhesion performance while improving solubility.
Solution Approach 2:
The patent creates a composite modified polyolefin structure by combining carboxyl-containing groups with the polyolefin backbone. This composite structure provides both the solubility characteristics needed for coating applications and the adhesion properties required for effective primer performance, resolving the contradiction between solubility and adhesion.
2Reliability
If chlorinated polyolefins are used as adhesion promoters, then adhesion is improved, but solubility in typical coating solvents deteriorates
Solution Approach 1:
The patent modifies the chemical parameters of the chlorinated polyolefin by introducing carboxyl groups through reaction with unsaturated carboxylic acids, anhydrides, or esters. This chemical modification fundamentally changes the solubility characteristics of the polymer, enabling it to dissolve in typical coating solvents while retaining the chlorine content necessary for adhesion promotion.
3Reliability
If crystalline polyolefins are modified with carboxylic acids to improve adhesion, then adhesion is improved, but solubility deteriorates due to crystalline nature
Solution Approach 1:
The patent changes the chemical parameters by introducing carboxyl groups and subsequently chlorinating the modified polyolefin. This dual modification approach overcomes the crystalline structure's resistance to solubility while maintaining adhesion properties, as the chemical modifications disrupt the crystalline packing and introduce polar groups that enhance solvent interaction.
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 modified polyolefins provide improved solubility and adhesion performance in both solvent- and water-based compositions, offering excellent adhesion and resistance to gasoline and humidity.
Implementation Method 1
reacting polyolefins with unsaturated carboxylic esters, unsaturated carboxylic acids, unsaturated carboxylic anhydrides, vinyl monomers, acrylic monomers, or mixtures thereof, to provide a carboxylated polyolefin
Implementation Method 2
The carboxylated polyolefins are then chlorinated by reaction with at least one chlorinating agent
Implementation Method 3
The chlorinated carboxylated polyolefins are then further modified by reaction with one or more polyfunctional alcohols
Data Source
AI summary
The present invention provides solvent- and water-based primer compositions that include at least one chlorinated carboxylated polyolefin that has been modified with one or more polyfunctional alcohols. The chlorinated carboxylated polyolefins are obtained by the reaction of polyolefins with at least one of unsaturated carboxylic esters, unsaturated carboxylic acids, unsaturated carboxylic anhydrides, acrylic monomers, and mixtures thereof then chlorinated. The chlorinated carboxylated polyolefins are then further modified by reaction with one or more polyfunctional alcohols. These polyfunctional alcohol-modified chlorinated carboxylated polyolefins may also contain pendant carboxyl groups, which have the propensity to form hydrophilic salts with amines or inorganic bases, thereby rendering the polyfunctional alcohol-modified chlorinated carboxylated polyolefins water-dispersible. These primer compositions are useful for significantly improving the adhesion of paints, adhesives, and inks to various plastic and metal substrates.