Polycarbonate film and sheet
1Key Takeaways
GB/T 35450—2017 Polycarbonate Film and Sheet This standard specifies the classification, requirements, test methods, inspection rules, marking, packaging, transportation, and storage of polycarbonate film and sheet. It applies to products made primarily from polycarbonate resin through extrusion and press-quenching or…
2Expert Interpretation
In-depth analysis of the National Standard of the People's Republic of China GB/T 35450-2017, covering the classification, requirements, test methods and implementation recommendations of polycarbonate films and sheets.
Interpretation of GB/T 35450—2017 Polycarbonate Film and Sheet Standard
Analysis of Standard Formulation Background and Technology Evolution
Polycarbonate (PC) is a high-performance engineering plastic that is widely used in electronics, automobiles, construction and other fields due to its excellent mechanical properties, optical properties and heat resistance. With the growth of market demand and technological progress, GB/T 35450—2017 "Polycarbonate Film and Sheet" came into being, aiming to standardize product quality and ensure its safety and reliability in various fields.
The formulation of this standard is based on the technological development of materials science and the plastics industry, combined with the experience of relevant domestic and foreign standards, and optimized for the characteristics of the Chinese market. By introducing advanced testing methods and quality control systems, GB/T 35450—2017 fills the gap in the standardization of domestic polycarbonate films and sheets.
Comparison and classification of standard frameworks
| Standard dimensions | GB/T 35450—2017 | ISO/TC 61 related standards | Industry custom standards |
|---|---|---|---|
| Classification basis | Use: ordinary grade, flame retardant grade, optical grade | Material properties: impact resistance, temperature resistance, optical properties | Specific industry requirements: such as food contact, medical use |
| Technical indicators | Thickness deviation, tensile strength, flame retardancy, dielectric strength, etc. | Elongation at break, thermal stability, insulation performance | Customized parameters: such as chemical corrosion resistance |
| Test methods | GB/T series test standards | ISO unified methods | Enterprise customized test process |
Core requirements and technical indicators interpretation
1. Appearance quality requirements
The appearance of polycarbonate film and sheet should be smooth and flat, and no impurities, scratches, holes, damage and other defects that affect the use are allowed. This requirement ensures the reliability and aesthetics of the material in subsequent applications.
2. Dimension deviation control
Thickness deviation and width deviation are important indicators for measuring product quality. For example, the allowable limit deviation for products with a nominal thickness of 0.100 mm is ±15%, while the limit deviation for products with a thickness greater than 0.250 mm is only ±6%. This strict control ensures the stability of the material during processing.
Test methods and quality inspection
The standard specifies a variety of test methods, including tensile properties testing, flame retardancy evaluation, dielectric strength measurement, etc. For example, when determining tensile strength, the specimens and test conditions specified in GB/T1040.3-2006 are used to ensure the accuracy and comparability of the data.
In addition, the standard also emphasizes the importance of specimen state conditioning, requiring at least 4 hours of state conditioning at a temperature of (23±2)°C and a relative humidity of (50±10)% to ensure the consistency of the test results.
Implementation Recommendations and Quality Control
- Raw Material Selection:Select high-quality polycarbonate resin and conduct strict raw material inspection to ensure that the basic material performance meets the requirements.
- Production Process Control:Starting from the extrusion calendering or cast molding process, optimize processing parameters such as temperature, speed and cooling method to reduce dimensional deviation and surface defects.
- Quality Inspection:Establish a complete quality inspection system, conduct sampling inspection on each batch of products according to standard requirements, and pay special attention to key indicators such as tensile strength, flame retardancy and light transmittance.