Specific Gravity (Density) of PETG
PETG (Polyethylene Terephthalate Glycol-Modified) is an amorphous transparent copolyester with high transparency, excellent toughness and easy processability.
Its basic density range is stable and unaffected by crystallization, with minimal density fluctuation of neat resin, and slight density changes brought by different modified types, with minor differences among different grades and modified types, as detailed below:
General-Purpose Neat PETG: 1.26～1.28 g/cm³, typical value 1.27 g/cm³, the most commonly used density standard for basic grades, suitable for most transparent products
High Transparency Food Grade PETG: 1.26～1.28 g/cm³, typical value 1.27 g/cm³, no additive residue, uniform density and in line with food contact safety requirements
Impact Modified PETG: 1.26～1.29 g/cm³, typical value 1.27 g/cm³, toughening agent addition has slight impact on density, mainly improving low-temperature impact resistance
Flame Retardant PETG: 1.27～1.30 g/cm³, typical value 1.28 g/cm³, halogen-free flame retardant system has small density increase, meeting environmental flame retardant requirements for electronic and electrical appliances
Glass Fiber Reinforced PETG (10%～20% Glass Fiber): 1.32～1.45 g/cm³, the higher the glass fiber content, the higher the density, used to enhance rigidity and dimensional stability
Mineral Filled PETG: 1.28～1.40 g/cm³, density is positively correlated with filler loading, focusing on cost reduction and molding shrinkage improvement
This density parameter is a core basis for the design of transparent packaging containers, electronic accessory enclosures, medical devices, cosmetic packaging, cards and sheet products. Its stable density and high transparency, high toughness properties make it widely used in products with high appearance and precision requirements. Density calculation is also key data for product weight control, mold design, assembly clearance matching and injection molding parameter setting, while supporting its core properties of high light transmittance, low haze and easy secondary processing.
