In the procurement and application of plastic raw materials, the physical property sheet (Datasheet) is the most intuitive reference tool. It not only demonstrates the performance parameters of the material, but also determines whether the product can meet the requirements of strength, heat resistance, electrical insulation and flame retardancy.
However, when many purchasers are confronted with a dense list of physical properties, they often only see the numbers but fail to understand the significance behind these figures. This article will provide you with a comprehensive interpretation of the plastic property table: covering the main performance categories, testing methods, and the practical significance of the numerical intervals, helping you quickly understand the material properties.
01 | Basic Physical Properties
Determine the lightweighting and dimensional stability of the material.
Density (g/cm³)
-Meaning: Reflects the weight of the material.
-Common ranges: พีพี ~0.90, เอบีเอส ~1.05, พีซี ~1.20.
-Customer concerns: Lightweight design (for automobiles and home appliances), transportation costs.
Water Absorption (%)
-Meaning: Reflects the degree of moisture absorption of the material.
-Common ranges: PA 6 can reach 2-3%, พีซี ~0.2%, and พีพี basically does not absorb water.
-The customer is concerned about: whether the size is stable and whether the electrical insulation is affected.
Mold Shrinkage (%)
-Meaning: The proportion of the formed part is reduced.
-Common ranges: PP 1.5-2.5%, เอบีเอส 0.4-0.7%, PC 0.5-0.7%.
-The customer is concerned about: the precision of the mold and whether the assembly matches.
02 | Mechanical Properties
Determine whether the material is "sturdy" or not.
Tensile Strength (Tensile strength, MPa)
-Meaning: The material's tensile strength.
-Range reference: PP ~30, ABS ~45, PC ~65, PA66-GF30 (glass fiber reinforced nylon) >150.
-Excellent standard: A strength greater than 80 MPa can be regarded as high strength.
-Test method: ASTM D638 / ISO 527.
Flexural Strength/Modulus
-Meaning: Reflects the ability to resist bending and deformation.
-Reference values: ABS ~70 MPa, PC ~90 MPa, and glass fiber reinforced nylon can reach over 200 MPa.
-Customers often ask, "Will the shell be soft and limp?"
Impact Strength (kJ/m²)
-Meaning: The ability to resist drops or impacts.
-Range reference: PS <5 (brittle), ABS ~20, PC without notch test can >600 (extremely impact-resistant).
-Excellent standard: > 50 kJ/m² = Excellent shock resistance.
-Test method: Izod/Charpy impact test.
Hardness (Rockwell/Shore)
-Meaning: Surface scratch resistance and wear resistance.
-Reference: PC and ABS are often around Rockwell R 100. For rubber products, check the Shore A hardness.
03 | Thermal Properties
Determine whether the material is "heat-resistant" or not.
Heat distortion temperature (HDT, ℃)
-Meaning: The temperature at which deformation begins when heated or compressed.
-Reference values: PP ~60℃, ABS ~85℃, PC ~130℃, PPS ~250℃.
-Excellent standard: Above 150℃, it can be used in the engine compartment and electrical components of automobiles.
Vicat Softening Point (℃)
-Meaning: The temperature at which a material begins to soften.
-Range: Usually slightly higher than HDT, such as PC Vicat point to 150℃.
Glass transition temperature (Tg, ℃)
-Meaning: The critical point at which a material changes from hard and brittle to rubber-like.
-Reference: PC ~145℃, PA6 ~50℃, PMMA ~105℃.
Melt flow index (MFR/MFI, g/10min)
-Meaning: Liquidity indicator.
-Interval explanation:
< 5 → Poor fluidity, high strength (suitable for thick-walled and structural components).
5-20 → General Grade (common range for ABS and PC).
> 30 → It has good fluidity and is suitable for thin-walled parts, but its strength decreases.
04 | Electrical Properties
Decide that the material is "absolutely insulating".
Dielectric Strength (kV/mm)
-Meaning: The capacity to withstand voltage per unit thickness.
-Reference value: For most engineering plastics, it is 15-30 kV/mm.
CTI Tracking Index (V)
-Meaning: Surface resistance to electric marks.
-Grade reference
≥600V → Excellent (high electrical safety grade)
400-599V → General household appliances
< 250V → Low-end application
Dielectric Constant (ε)
-Meaning: The lower the value, the better the insulation performance.
-Reference: PP ~2.2 (excellent insulation), PC ~3.0-3.2.
05 | Flame Retardant Properties
Determine whether the material is "fire-resistant" or not.
UL 94 flame retardant grade
-Grade sequence: 5VA ≈ V-0 > V-1 > V-2 > HB.
-Application significance
V-0 → Can be used in electronic appliances;
HB → Only general requirements.
-Note: The grade will change with different thicknesses.
Ignition temperature of hot wire (GWIT, ℃)
-Meaning: The ability to resist the ignition of high-temperature metal parts.
-Reference values: Commonly 750℃ and 850℃, and high-end materials can reach 960℃.
06 | Processing & Dimensional Stability
Determine whether the workpiece is precise and reliable.
Shrinkage rate (%)
-Range: PP 1.5-2.5%, PC/ABS ~0.5%.
-Excellent standard: < 1% shrinkage rate = dimensional stability.
Coefficient of linear expansion (CLTE, ×10⁻⁵/℃)
-Meaning: Dimensional changes under temperature variations.
-Reference: PC ~6.5, PA66-GF30 ~2.0 (glass fiber reinforcement can significantly reduce).
07 | How to make Good Use of the Physical Property Table?
Ask "Is it firm?" → Check the tensile, bending and impact strength
Ask "Is it heat-resistant?" → Check HDT and Tg
Ask "Can it be used in electrical appliances?" → Check CTI and UL94
Ask "Will the size change?" → Check the shrinkage rate and water absorption rate
08 | Frequently Asked FAQs by Customers
Q1: Does high impact strength necessarily mean better?
A: Not necessarily. Materials with high impact strength have good toughness, but may lack rigidity. For instance, PC is very shock-resistant, but it is less rigid than PA66. It depends on the application requirements.
Q2: Does a high melt index mean it is easy to process?
A: Yes, but excessive fluidity can also lead to a decrease in the strength of the product. It is usually necessary to balance processing efficiency and mechanical properties.
Q3: How to quickly judge the quality of materials?
A: First, look at the application requirements (strength/heat resistance/flame retardancy/dimensional accuracy), and then compare them with the numerical range in the physical property table. A high individual indicator does not necessarily mean the overall best.
09 | Conclusion: The Value of Juyuan
The physical property table data itself is only for reference. The actual material selection should be combined with the application scenario, process adaptation and cost control. As an international plastic raw material trader, Juyuan not only provides original factory data but also offers comparison recommendations based on the actual needs of customers, helping purchasers find suitable materials more quickly.