Polymer Film Guide- Amorphous vs. Semi-Crystalline Films
Comments Off on Polymer Film Guide- Amorphous vs. Semi-Crystalline FilmsResearching polymer films can be a difficult task, especially since there is many different grades, resins, and combinations available. However, breaking down polymer films by molecular structure: amorphous or semi-crystalline can help narrow down the selection to films that will meet property requirements, difficulty of fabrication, and their relative cost.
The difference between amorphous & semi-crystalline film
Semi-crystalline films have a highly ordered molecular structure with sharp melt points. While amorphous polymers soften gradually when the temperature rises, semi-crystalline plastics do not. Instead, they remain solid until a certain quantity of heat is absorbed. The materials then quickly change into a low viscosity liquid. However, the sharp melting point of semi-crystalline polymers makes them difficult to thermoform, but ideal for applications that require a high strength, low friction plastic.
Amorphous
- Softens over a broad range of temperatures
- Easy to thermoform
- Tend to be translucent or transparent
- Bond well using adhesives & solvents
- Prone to stress cracking
- Poor Fatigue Resistance
Semi-Crystalline
- Sharp Melting Point
- Difficult to thermoform
- Difficult to bond using adhesives & solvents
- Good resistance to stress cracking
- Good Fatigue Resistance
Imidized
- Best physical properties above 500ºF
- Best temperature resistance
- Good chemical resistance
Types of amorphous polymer films
Commodity
- ABS
- Acrylic
- PVC
- Polystyrene
Engineering
- TPU
- Polycarbonate
- Modified PPE
Types of semi-crystalline polymer films
Commodity
- PMP
- Polypropylene
- HDPE
- LDPE
Engineering
Types of imidized polymer films
Amorphous polymers that have exceptional mechanical, thermal and chemical resistant properties
- Polyamide-imide (PAI)
- Polybenzimidazole (PBI)
- Polyimide (PI)
CS Hyde Company stocks and converts a variety of high performance and engineering films. We also laminate PSA adhesive to hard to bond semi-crystalline films, ideal for peel and stick bonding applications. To learn more about each of the films view our high performance film catalog, or contact us for additional information.