URETHANE RUBBER


Introduction

  UR SERIES is Polyester urethane rubber, which is an easy to process millable gum especially developed for improved compounding and processing benefits. It can be Processed and compounded by the use of conventional rubber manufacturing equipment and techniques to yield finished urethane parts.

TYPICAL POLYMER PROPERTIES
Chemical type
Polyester urethane
Physical form
Solid
Color
White to cream
Odor
Faint, characteristic
Specific gravity
1.15
Mooney
viscosity
ML 1-4 at 100oC
35-65
Storage stability
Excellent
Health hazard
None

Typical Physical Properties
Series Nr. MPU50 MPU60 MPU70 MPU80 MPU90
Hardness, A 50 60 70 80 90
Tensile Strength, psi 3900 3360 2820 1830 1100
300% Modulus, psi 480 580 1100 1400 900
Elongation, % 700 640 600 420 310
Tear ( Die C) pli 180 220 245 270 165
Compression Set
22hts. @ 158oF ( )		 49 62 70 96 98

MOLDING

    Compounds of URETHANE RUBBER can be molder by compression, injection and transfer molding procedures. Excellent mold definition is obtainable in press cures. The linear shrinkage of vulcanized of UR varies somewhat with the type of loading, but in general this value is approximately 1.5%, which is comparable to that of neoprene.

    Optimum press cures are obtained with peroxide curing system, temperatures from 305 oF to 340 oF with cycles ranging from 45 to 5 minutes.

    Excellent mold release is provided by lubricant of M-7 or silicone mold release lubricants, but indiscriminate use can cause poor flow and knitting problems.

Notice: These values are based on the test of our present laboratory test specimens