Differences Between PVDF Heat Shrink Tubing and Conventional Heat Shrink Tubing: A Comparison of Material Properties and Electrical/Electronic ApplicationsIn fields such as electrical/electronics, chemical engineering, and new energy, heat shrink tubing serves as a critical protective material, with its performance directly impacting equipment reliability and lifespan. PVDF (polyvinylidene fluoride) heat shrink tubing and conventional heat shrink tubing (e.g., PVC, PE-based) exhibit significant differences in material properties and application scenarios. This article conducts a comparative analysis from four aspects: shrinking process, weather resistance, mechanical strength, and electrical/electronic applicability.

I. Shrinking Process: Crosslinking Technology Determines Conformity Precision

PVDF Heat Shrink Tubing: It uses an irradiation crosslinking process, where high-energy radiation forms a three-dimensional network structure in the molecular chains. After heating, it achieves a shrink ratio of 2:1 to 3:1, enabling tight conformity to irregular surfaces (e.g., cable joints, solder joints) without bubbles or wrinkles post-shrinking. Its wide shrinking temperature range (120°C–150°C) makes it suitable for processing with handheld hot air guns or automated equipment.

Conventional Heat Shrink Tubing: Most use chemical crosslinking or thermoplastic shrinking processes, with a typical shrink ratio of 1.5:1 to 2:1. They are prone to local deformation due to uneven temperature during shrinking. For example, PVC heat shrink tubing may soften and adhere at high temperatures, compromising protective performance.

II. Weather Resistance: Fluorine Elements Endow Long-Term Stability

PVDF Heat Shrink Tubing: The C-F bonds in its molecular structure have high bond energy, providing strong resistance to environmental factors such as ultraviolet (UV) radiation, ozone, and salt spray. After long-term outdoor exposure, the attenuation rates of its mechanical properties and electrical insulation properties remain below 5%, making it suitable for harsh environments like marine engineering and photovoltaic power stations.

Conventional Heat Shrink Tubing: PVC materials tend to age and become brittle under UV exposure, while PE materials have insufficient heat resistance (typically only up to 105°C). Long-term outdoor use may lead to issues such as cracking and reduced insulation performance.

III. Mechanical Strength: Abrasion and Tear Resistance

PVDF Heat Shrink Tubing: It has a tensile strength exceeding 30 MPa and an elongation at break of up to 150%, combining flexibility and tear resistance. Its high surface hardness enables resistance to external forces such as mechanical friction and cutting, making it suitable for vibration-prone scenarios like motors and transformers.

Conventional Heat Shrink Tubing: PVC heat shrink tubing has lower hardness and is easily scratched by sharp objects; while PE material has some toughness, it is prone to deformation under prolonged stress, leading to protection failure.

IV. Applicability in Electrical/Electronic Fields: Tests of High-Temperature and Chemical Environments

1. Comparison of Temperature Resistance

PVDF Heat Shrink Tubing: It has a long-term operating temperature of up to 175°C and can tolerate higher temperatures in the short term, making it suitable for high-temperature areas such as automotive engine compartments and industrial heating equipment. Its high heat deflection temperature prevents loosening or cracking due to temperature fluctuations.Conventional Heat Shrink Tubing: PVC heat shrink tubing typically has a maximum temperature resistance of 105°C and is prone to softening and deformation in high-temperature environments; PE material has even poorer temperature resistance and is only suitable for normal temperature environments.

2. Chemical Corrosion Resistance

PVDF Heat Shrink Tubing: It exhibits strong resistance to media such as acids, alkalis, and oils, and does not swell or age when in contact with industrial oils like lubricating oils and hydraulic oils. This characteristic makes it suitable for corrosive environments such as chemical equipment and lithium battery modules.Conventional Heat Shrink Tubing: PVC material tends to decompose when exposed to strong acids and alkalis; PE material has weaker resistance to oil-based media and may lose adhesion after prolonged immersion.

3. Insulation and Protective Functions

PVDF Heat Shrink Tubing: It has a dielectric breakdown strength exceeding 30 kV/mm and a volume resistivity greater than 10¹⁴ Ω·cm, effectively blocking current leakage. The dense covering layer formed after shrinking provides moisture and dust resistance, along with flame retardancy (certified by UL VW-1).Conventional Heat Shrink Tubing: Its insulation performance degrades with aging, and flame retardancy typically only meets the UL 94 V-2 standard, potentially releasing harmful gases in high-temperature environments.