Material characteristics of medical grade polyvinyl chloride (PVC)

Medical-grade polyvinyl chloride (PVC), as a widely used polymer material in the healthcare field, exhibits the following material characteristics across four key dimensions: physical properties, chemical properties, biological performance, and processing capabilities:

I. Physical Properties

1. Flexibility-Strength Balance:

   • Adjustable hardness through plasticizers (e.g., DEHP), enabling flexible conversion between soft (for blood bags, IV tubes) and rigid forms (for packaging shells).
   • Tensile strength: 20-50 MPa; elongation at break: 100%-400%, meeting diverse medical application requirements.

2. Transparency & Colorability:

   • Processable into transparent/semi-transparent forms for blood visibility.
   • Customizable colors via additives like titanium dioxide and phthalocyanine blue.

3. Low-Temperature Performance:

   • Excellent cold resistance (-20°C to 60°C), suitable for cold-chain logistics and extreme climates.

II. Chemical Properties

1. Chemical Resistance:

   • Highly resistant to oxidizers, reducers, strong acids (e.g., HCl, H₂SO₄), and most organic solvents (e.g., ethanol, isopropanol), preventing reactions with blood components.

2. Barrier Properties:

   • Low permeability to O₂ and CO₂, preserving blood component integrity.
   • Superior water vapor resistance, preventing moisture-induced deformation in blood bags.

III. Biological Performance

1. Blood Compatibility:

   • Hemolysis rate <0.5% (national standard requirement); clotting time meets clinical criteria for transfusion safety.
   • Excellent compatibility with anticoagulants (e.g., heparin), avoiding coagulation upon blood contact.

2. Biocompatibility:

   • Plasticizer migration <15 mg/100 mL (GB/T 15593-2020 standard), preventing toxin release into blood.
   • Passes ISO 10993 biocompatibility tests (non-cytotoxic, non-sensitizing, non-carcinogenic).

3. Sterilization Compatibility:

   • Resistant to high-pressure steam (121°C, 20 min), ethylene oxide, and γ-ray sterilization, ensuring aseptic conditions.