Page 313 - Engineering Plastics Handbook

Polyamide-imide (PAI) 273

Torlon 4000T is greater than 90% imidized and has molecular weight
ranges designed advantageously for compounded products which are
utilized for injection-molding and extrusion processes. It is the neat resin
powder utilized in the compounded grades discussed below. The diamines
used in the synthesis of this resin provide flexibility, toughness, and melt
processability. In addition, this polyamide-imide can be used in tough coat-
ing, adhesive, and additive applications. Torlon 4000TF is a fine-particle-
size version of Torlon 4000T. It has a median particle size around 25 µm,
and 95% of the powder is less than 75 µm. This defined particle size is
advantageous in additive applications, compression moldings, powder
coatings, and dispersions.

Torlon compounds
Torlon 4203L is an unreinforced, all-purpose grade, and it contains 3%
titanium dioxide and 0.5% fluoropolymer. It has the best impact resist-
ance and greatest elongation of all the Torlon compounds.
Torlon 4301 is one of three current friction and wear grades. This
polyamide-imide resin is designed as a general-purpose, low-friction, and
low-wear compound. The resin composition contains graphite and flu-
oropolymer. It is engineered to meet the needs of the bearing manufac-
turer with high strength, performance at elevated temperatures to
260°C, and excellent chemical resistance.
Torlon 4275 polyamide-imide resin is designed as a low-friction and
low-wear compound, similar to Torlon 4301 resin with better perform-
2
ance at higher velocities and pressures up to 50,000 ft⋅lb/(min⋅in ). The
resin composition contains graphite and fluoropolymer. Its high
strength, performance at temperatures up to 260°C, and excellent chem-
ical resistance make this grade an excellent choice for demanding rotat-
ing and sliding applications.
Torlon 4435 polyamide-imide resin is specifically designed to provide
exceptionally low-wear performance in nonlubricated applications even
at high pressure and velocity (PV) conditions greater than 50,000
ft⋅lb/(min⋅in). The low coefficient of thermal expansion provides the
ability to meet close tolerances over a wide temperature range. Due to
its electrically dissipative property, this grade may also be considered
for antistatic functions.
There are two fiber-reinforced strength grades. Torlon 5030 is a 30%
glass fiber reinforced polyamide-imide resin. The material exhibits high
strength and stiffness, retention of stiffness at temperatures up to
260°C, and very low creep. Torlon 7130 is a polyamide-imide compound
containing 30% carbon fiber reinforcement. This melt-processable, high-
performance engineering thermoplastic has extraordinary strength and
stiffness at temperatures up to 260°C. It has the best fatigue resistance
of all the Torlon grades.