Society of Plastics Engineers
Common Thermoforming questions and helpful references.
http://thermoformingdivision.com/
Plastic Sheet Extruders
Spartech
http://www.spartech.com/
Primex Plastics
http://www.primexplastics.com/
Kydex LLC
http://www.kydex.com/
Allen Extruders
http://www.allenx.com/
Southtech Decro
http://www.southtechdl.com
Orion Plastics
http://orionplastics.com/
Boltaron
https://www.boltaron.com/
Local Suppliers
Port Plastics
http://www.portplastics.com/
Laird Plastics
http://www.lairdplastics.com/
Professional Plastics
http://www.professionalplastics.com/