411 2Urethane (Ether Type, Ester Type) Property Comparison 2Discoloration of Urethane Urethane may experience discoloration and yellowing with age. Urethane turns yellow by aging, but physical property or characteristics remain unchanged. Discoloration is distinct especially with antistatic urethane and Vulkollan®. See the explanation below. Vulkollan® has poorer color stability against ultraviolet rays than general urethanes due to its unique composition. Pictures below show the process of change in colors of a sample exposed to outdoor sunlight. * No change in physical property or characteristics due to discoloration. Before Test 1 day 6 days 20 days t %JTDPMPSBUJPO PG 7VMLPMMBO® t "HJOH %JTDPMPSBUJPO PG "OUJTUBUJD 6SFUIBOF Before After * Time to turn yellow and level of yellowing vary depending on operating environment, etc. Properties Ether Type (Shore A95, 90) Ester Type (Shore A70, 50, 30) Tensile Strength OK Elongation OK Tear Strength OK Impact Resilience OK Abrasion Resistance Slip Wear OK Shock Wear OK Hydrolysis Resistance OK Oil Resistance OK Strength OK Durability OK Acid Resistance, Alkali Resistance OK 2Urethane Properties Item Unit Urethane Standard Vulkollan® Abrasion Resistant Ceramic Urethane Heat Resistant Low Rebound Extra Low Hardness Hardness Shore A 95 90 70 50 30 92 68 90 70 95 90 70 50 90 70 15 Specific Gravity - 1.13 1.13 1.20 1.20 1.20 1.26 1.20 1.13 1.13 1.20 1.15 1.13 1.03 1.02 Tensile Strength MPa 44 27 56 47 27 46.5 60 44.6 31.3 42 26 53 45 44.6 11.8 0.6 Elongation % 380 470 720 520 600 690 650 530 650 360 440 680 490 530 250 445 Heat resistance °C 70 80 (120 deg. for Short Time) 70 70 70 120 70 80 Low Temp. Resistance °C -40 -20 -20 -20 -40 -20 -20 -20 -40 &The characteristic values of tensile strength and elongation are tested based on the JIS standard K6251. t Characteristic Values of Antistatic Urethane (Test Conditions: Temperature 30°C Humidity 60%) &All other properties are equal to those of urethane of the same hardness. Specific Volume Resistivity 2.1x108Ω t cm Surface Resistivity 4.0x109Ω 2Features of Various Urethanes Material Features Standard Urethane Ether / Ester Polyurethane Excels in strength in repeat use and shock-absorbing properties. Can be used for applications such as Mechanical Stoppers. Ester Type is Hydrolytic. Do not use in humid and wet areas. Antistatic Urethane Excels in antistatic effect. Can be used where mechanical strength and anti-static measures are required. Heat Resistant Urethane CThis urethane has up to 120°C heat resistance. (70 deg. for the standard urethane) Suitable for use in applications where high material strength in high-temperature range is required. Super Abrasion Resistant Urethane (Vulkollan®) Vulkollan® is a super abrasion resistant urethane which is far superior to conventional urethanes in abrasion resistance and load bearing. Excels in tearing strength. 6 times higher in abrasion resistance and 1.5 times in material strength than the standard urethane. Abrasion Resistant Urethane Unique composition realized abrasion resistance 2.5 times higher than standard urethane at low cost. Helps to reduce the exchange frequency. Color is dark brown. Ceramic Urethane These MISUMI original urethane sheets are unique mixture of ceramic particles. Vulkollan® and Wear Resistant Urethane have resistant property against "surface", and the Ceramic Urethane has resistance against "line". Compared to the Standard Urethane and various rubbers, the Ceramic Urethane is relatively smooth in its machined surfaces though it is lower in hardness. Note that cutting due to contact may cause dust. t 5BCFS "CSBTJPO 5FTU 3FTVMUT Material Test Standard Urethane Super Abrasion esistant Vulkollan® Abrasion Resistant Urethane Ceramic Urethane Abrasion Test (Taber Method) 197.3 33.9 73.8 101 Abrasion Volume (mm3) Testing Method JIS K 7204: 1999 "Plastics - Determination of Resistance to Wear by Abrasive Wheels" Abrasive Wheel: H, 22 Load: 9.8N Number of Strokes: 1,000 Test Parameter: 1 &The values are not guaranteed but measured ones. 2Features of Ceramic Urethane t Deflection Comparison of Standard Urethane and Ceramic Urethane Deflection between the ceramic urethane and the standard urethane differs when the same load is applied. Careful consideration should be given for replacement. t &OMBSHFE 7JFX PG $FSBNJD 6SFUIBOF t $IBOHF BGUFS $FSBNJD 6SFUIBOF JT .BDIJOFE Change after ceramic urethane round bar is machined (Lathe: 600rev/min.) for 2 minutes. Please be advised that white section seen on the photo is ceramic powder particles occurring during the manufacturing process. These micro-particles are very fine not to create any surface roughness even when they fall off. (Close-up: x5,000) Compression, Deflection Comparison Shore A 0 1 2 3 4 5 6 7 8 9 10 11 12 13 0 1 2 3 4 5 Load (kN) Deflection (mm) 50°Ceramic Urethane 50°General Urethane 70°Ceramic Urethane 70°General Urethane 90°General Urethane 90°Ceramic Urethane 95°Ceramic Urethane 95°General Urethane F 20mm Ø20 Cylinder Before Machining After Machining 10μm Urethane, Rubbers and Sponges Features of High Performance Urethane and Rubber
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