PolyGrid™
Precision-Expanded Plastics
Materials Advantages / Disadvantages
Polyethylene
Polytetrafluoroethylene (PTFE)
Polyfluoroethylenepropylene (PFEP)
Polyvinyl Chloride (PCV)
Polysulfones
Polypropylene
Polyvinyl Fluoride
Polyamide (Nylon)
Polychlorotrifluoroethylene (PCTFE)
Fantastically Flexible
PolyGrid™
Polyethylene
Advantages:
1. Low cost (except UHMWPE)
2. Excellent dielectric propeties
3. Moisture resistance
4. Very good chemical resistance
5. Available in food grades
6. Processable by all thermoplastic methods (except HMWHPE and UHMWPE)
Disadvantages:
1. High thermal expansion
2. Poor weathering resistance
3. Subject to stress cracking (except UHMWPE)
4. Difficulty in bonding
5. Flammable
Polytetrafluoroethylene (PTFE)
Advantages:
1. Nonfammable
2. Outstanding chemical and solvent resistance
3. Excellent weatherability
4. Low friction coefficient (antistick property)
5. Wide thermal service range
6. Very good electrical properties
Disadvantages:
1. Not processable by common thermoplastic methods
2. Toxic in thermal degradation
3. Subject to creep
4. Permeable
5. Requires high processing temperatures
6. Low Strength
7. High density
8. Comparativey high cost
Polyfluoroethylenepropylene (PFEP)
Advantages:
1. Processable by normal thermolastic methods
2. Resistant to chemical (including oxidizing agents)
3. Excellent solvent resistance
4. Antistick characteristics
5. Nonflammable
6. Low coefficient of friction, dilectric constant, mod shrinkage, and water absorption.
Disadvantages:
1. Comparatively high cost
2. High density
3. Subject to creep
4. Low compressive and tensile strength
5. Low stiffness
6. Toxic upon thermal decomosition
Polyvinyl Chloride (PCV)
Advantages:
1. Processable by thermoplastic methods
2. Wide range of flexibility (by varying levels of plasticizers)
3. Nonflammable
4. Dimenional stability
5. Comparatively low cost
6. Good resistance to weathering
Disadvantages:
1. Subject to attach by several solvents
2. Limited thermal capability
3. Thermal decomposition evolves HC1
Polysulfones
Advantages:
1. Good thermal stability
2. Excellent high-temperature creep resistance
3. Transparent
4. Tough and rigid
5. Processable by thermoplastic methods
Disadvantages:
1. Subject to attack by many solvents
2. Poor weatherability
3. Subject to stress cracking
4. High processing temperature
Polypropylene
Advantages:
1. Processable by all thermoplastic methods
2. Low coefficient of friction
3. Excellent electrical insulation
4. Good fatigue resistance
5. Excellent moisture resistance
6. First rate abrasion resistance
7. Good grade availability
8. Service temperature to 126 C (260 F)
9. Very good chemical resistance
10. Excellent flexural strength
11. Good impact strength
Disadvantages:
1. Broken down by ultraviolet radiation
2. Poor weatherability
Polyvinyl Fluoride
Advantages:
1. Processable by thermoplastic methods
2. Low permeability
3. Flame retardance
4. Good solvent resistance
Disadvantages:
1. Lower thermal capability than highly fluorinated poymers
2. Toxic (in thermal decomposition)
3. High dipole bond
4. Subject to attack by strong acids
Polyamide (Nylon)
Advantages:
1. Tough, strong and impact resistant
2. Low coefficient of friction
3. Abrasion resistance
4. High Temperature resistance
5. Processable by thermoplastic methods
6. Good solvent resistance Ð ÒmostÓ
7. Resistant to bases
Disadvantages:
1. High moisture absorption with related dimensional instability
2. Subject to attack by strong acids and oxidizing agents
3. Requires ultraviolet stabilization
4. High shrinkage in molded sections
5. Electrical and mechanical properties infuenced by moisture content
Polychlorotrifluoroethylene (PCTFE)
Advantages:
1. Excellent solvent resistance
2. Optically clear
3. Zero moisture absorption
4. Self-extinguishing
5. Low permeability
6. Creep resistance better than PTFE of PFEP
7. Very low coefficie3nt of friction
8. Good low temperature capability
Disadvantages:
1. Lower electrical properties than PTFE
2. More difficult to mold than PFEP
3. Crystallizes upon slow cooling
4. Less solvent resistance thanb PTFE and PFEP
5. Higher coeffiecient of friction than PTFE and PFEP