Elder Engineering - Plastics Engineering

Cross Linked Polystyrene / Q200.5

Q200.5 is a unique cross linked polystyrene microwave plastic.

Dielectric Properties
Outstanding! Maintains a Dielectric Constant of 2.53 through 500Ghz with extremely low dissipation factors. Ideal for microwave lenses, microwave circuitry, antennae, coaxial cable connectors, sound transducers, television satellite dishes and sonar lenses. Other applications include nondestructive material testing devices, surveillance equipment, radar windows, radomes and missile guidance system housings. One interesting application for radar is mapping the Earth's surface from fast aircraft at high altidudes.

High Voltage Insulators
Ability to withstand high voltage is important for producing gap switch houses, capacitors and other components.Q200.5 has proven superior to Acrylics, Epoxies, Urethanes and other plastics for dendriting resistance. (Failure caused by electron bombardment).

Radiation Resistance
Superior to most plastics. Little change in dielectric loss over a wide range of exposures up to 1000M rads. Superior resistance to mechanical deterioration by ionizing radiation.

Rigidity and Dimensional Stability
Q200.5 exhibits no permanent deformation or plastic flow under normal loads. All castings are stress-free, and do not require stress relieving prior to, during or after machining.

Optical
Transmission approximately equal to Acrylic - (87% visible light, 1" thick). Refractive index 1.59 @ 589 nanometers, 1.604 @ 486 nanometers and 1.585 @ 656 nanometers. Utilized in combination with Acrylic lenses for colour correction.

Sound Transmitting
Excellent acoustic properties having an impedence close to water. Velocity 93 x 10³ inches per second. Ideal for sonar lenses.

Out Gassing
Negligible at room temperatures Nasa values at elevated temperatures are: Total Mass Loss (TML) .14/.16% Collected Volatile Condensable Materials (CVCM) .02%

Water Absorption
Less than .08%, unfilled Q200.5, has been immersed in boiling water for 1000 hours without change in dielectric constant.

Machinability
Handles well in all machining operations. Tool configuration is similar to those used on Acrylic. Due to high resistance to cold flow and freedom from stress, it is easily machined or laser beam cut to very close tolerances. Accuracies of .0001 can be obtained by grinding. Crazing can be avoided by using sharp tools and avoiding excessive heat during polishing. Stress relieving is not required before, during of after machining.

Chemical Resistance
Alkalies, Alcohols, Aliphatic Hydrocarbons and mineral acids have no effect. Aromatic & chlorinated hydrocarbons cause swelling and should be avoided.

Light Weight
15% lighter than Acrylic and less than half of TFE {Teflon). Specific Gravity is 1.05.

Subzero Properties
Maintains a Dielectric Constant of 2.55 dissipation factor. At -270 Centigrade the dissipation factor is .00019

Environmentally Friendly

Non hazardous; contains no ingredients harmful to the environment.

Military Specification
Q200.5 conforms to military specification LP-516A, type E2, formerly known as MIL-P-77C-E2.

Flammability
The Q200.5 burn rate is less than one inch per minute.

Standard Shapes and sizes
Q200.5 rod from .030" to 9" in diameter.
Q200.5 sheet from .010" to 6" thick.

Rings, tubes, large rods and sheets are available upon request.