Block Copolymer Coating for Catheter Lubricity and Durability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Medical devices inserted in vivo, such as catheters and guidewires, face challenges in maintaining both lubricity and durability, especially in complex and narrow lesion areas, where existing hydrophilic polymer coatings tend to peel off or lose effectiveness under mechanical stress.
Innovation Solution
A medical device with a surface lubricating layer formed from a block copolymer having a hydrophilic portion and a hydrophobic portion with a reactive functional group, where the existence ratio of the hydrophobic portion in the outermost surface is between 20 to 45 mol% and the solution viscosity of the block copolymer is within 8 to 30 mPa·s, providing both excellent lubricity and durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a hydrophilic polymer coating is applied to improve lubricity, then the device can be inserted more easily into blood vessels, but the coating tends to peel off under mechanical stress
Solution Approach 1:
The patent applies composite materials by combining hydrophilic polymer segments (providing lubricity) with hydrophobic polymer segments containing reactive functional groups (providing durability through crosslinking). This creates a surface lubricating layer that integrates both lubricating and durable properties in a single coating structure, resolving the contradiction between ease of operation and reliability.
Solution Approach 2:
The patent changes the chemical and physical parameters of the coating by controlling the molecular weight, composition ratio, and crosslinking degree of the block copolymer. By adjusting these parameters, the coating achieves optimal balance between lubricity (from hydrophilic segments) and durability (from crosslinked hydrophobic segments), preventing peeling while maintaining smooth insertion.
2Adaptability or versatility
If the medical device is made smaller and thinner to access narrow lesion areas, then the device can reach more complex anatomical locations, but the surface lubricity and durability become harder to maintain
Solution Approach 1:
The patent applies local quality by concentrating the functional properties at the surface level rather than throughout the entire device structure. The surface lubricating layer with controlled thickness provides localized lubricity and durability exactly where needed (at the interface with body tissues), allowing the bulk device to remain small and thin while maintaining surface performance.
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 enables a medical device with a surface lubricating layer that maintains excellent lubricity and durability, preventing peeling and ensuring effective operation in complex anatomical environments without compromising durability or lubricity.
Implementation Method 1
immersing a base layer of a medical device in the polymer solution to cause swelling
Implementation Method 2
further crosslinking or polymerizing the polymer on the base layer surface
Implementation Method 3
further crosslinking or polymerizing the polymer on the base layer surface
Implementation Method 4
epoxy groups can be crosslinked by a heating operation
Implementation Method 5
epoxy groups can be crosslinked by a heating operation
Data Source
Figure 1~2
Figure 3
AI summary
The invention provides a medical device including a lubricating coating film (surface lubricating layer) that exerts excellent lubricity and durability. The medical device of the invention includes, on a base layer, a surface lubricating layer formed from a block copolymer having a hydrophilic portion and a hydrophobic portion that bears a reactive functional group. The existence ratio of the hydrophobic portion of the block copolymer in an outermost surface of the surface lubricating layer is 20 to 45 mol%, and the viscosity of a 1 wt% chloroform solution of the block copolymer in an environment at a temperature of 30°C is 8 to 30 mPa·s.