Phenyl silicone rubber exhibits excellent high-temperature resistance, biocompatibility, and mechanical stability in medical catheter applications, making it an important material choice in the field of high-end medical catheters, especially for medical scenarios requiring resistance to extreme temperatures and long-term implantation.
I. Matching the Characteristics of Phenyl Silicone Rubber with Medical Catheter Requirements
1. Core Characteristics of Phenyl Silicone Rubber
Wide Temperature Range Elasticity: Maintains elasticity continuously in the range of -100℃ to +70℃, far superior to traditional silicone rubber.
Ultra-High Heat Resistance: The conjugated double bond structure of the benzene ring in the molecular chain absorbs thermal energy, significantly improving thermal stability, with heat resistance reaching 250-300℃, much higher than ordinary silicone rubber (approximately 200℃).
Excellent Biocompatibility: Meets biomedical requirements, is non-toxic and odorless, and does not contain harmful soluble substances (such as lead, cadmium, arsenic, etc.), meeting the biocompatibility standards for medical devices.
Low Compression Set: Maintains a low compression set rate even under prolonged pressure or heat, ensuring stable sealing performance.
Chemical Stability: Stable against various chemical substances and resistant to erosion by blood, drugs, and disinfectants.
2. Key Performance Requirements of Medical Catheters
As a Class III high-risk medical device, medical catheters must meet the following core requirements:
Biocompatibility: Does not cause inflammation, allergies, or carcinogenic reactions, and maintains stable physical properties during long-term implantation.
Mechanical Adaptability: Possesses both flexibility (to facilitate passage through tortuous anatomical paths) and appropriate rigidity (to prevent collapse or kinking during operation).
Disinfection Resistance and Stability: Can withstand high temperature and irradiation sterilization conditions, and has stable chemical properties.
Functional Reliability: Ensures that it can withstand sufficient tensile force during clinical use, preventing breakage or detachment.

II. Specific Applications of Phenyl Silicone Rubber in Medical Catheters
1. Special Medical Catheter Applications
Long-Term Implantable Catheters: Due to its excellent aging resistance and biocompatibility, phenyl silicone rubber is particularly suitable for catheters implanted in the human body for long periods, such as central venous catheters and urinary catheters. High-Temperature Resistant Catheters:  These catheters excel in catheter systems requiring resistance to high-temperature sterilization, withstanding multiple high-temperature sterilization cycles without performance degradation.
Precision Interventional Catheters: Used in precise medical procedures such as vascular intervention and neurointervention, their stable physical properties ensure precise control during complex procedures.
2. Advantages Compared to Traditional Materials
Table
Characteristic | Phenyl Silicone Rubber | Ordinary Silicone Rubber | Polyurethane (PU) | Polyvinyl Chloride (PVC)
Temperature Resistance Range | -100℃ to +70℃ | -60℃ to +40℃ | -40℃ to +60℃ | -15℃ to +40℃
Biocompatibility | Excellent | Excellent | Good | Fair
Flexibility | Excellent | Excellent | Excellent | Good
Chemical Resistance | Excellent | Excellent | Good | Fair
Long-Term Implantation Stability | Excellent | Good | Good | Fair
Processing Difficulty | Medium | Low | High | Low

III. Technical Challenges and Solutions
1. Limitations of Traditional Silicone Rubber Catheters
Soft and easily deformed: Traditional silicone rubber catheters are prone to bending and deformation during clinical procedures, affecting insertion accuracy.
Excessive tensile properties: The catheter is prone to longitudinal stretching and deformation during insertion and removal, causing patient discomfort.
2. Innovative Application Solutions of Phenyl Silicone Rubber
Embedded Guidewire Design:  A non-elastic guidewire (medical plastic or metal) is axially embedded inside the phenyl silicone rubber catheter, forming a single-lumen or multi-lumen structure. This retains the flexibility of silicone while preventing stretching and deformation.
Molecular Structure Optimization: By precisely controlling the amount and distribution of phenyl groups, the hardness and tensile properties of the silicone rubber are adjusted to meet different clinical needs.
Surface Modification Technology: Combining chemical grafting technology, functional graphene is prepared using silane coupling agents to modify graphene oxide, and then compounded with phenyl silicone rubber to improve the surface properties of the catheter.