Blends of PU with conventional rubbers.Polyurethane polyurethane Any of a class of very versatile polymers that are made into flexible and rigid foams, fibres, elastomers (elastic polymers), surface coatings, and adhesives. rubber is a specialty rubber that finds use in many common rubber articles such as skate skate, fish: see ray. skate Any of nine genera (suborder Rajoidea) of rounded to diamond-shaped rays. These bottom-dwellers are found from tropical to near-Arctic waters and from the shallows to depths of more than 9,000 ft (2,700 m). wheels, conveyor belts conveyor belt One of various devices that provide mechanized movement of material, as in a factory. Conveyor belts are used in industrial applications and also on large farms, in warehousing and freight-handling, and in movement of raw materials. , rubber covered rolls and other applications where urethane urethane (yoor´ithān´), n ethyl carbamate used as an anesthetic agent for laboratory animals, formerly used as a hypnotic in humans. is used because of its properties. Urethane rubber compounds possess a unique combination of excellent abrasion abrasion /abra·sion/ (ah-bra´zhun) 1. a rubbing or scraping off through unusual or abnormal action; see also planing. 2. a rubbed or scraped area on skin or mucous membrane. resistance, excellent oil resistance, high tensile tensile, adj having a degree of elasticity; having the ability to be extended or stretched. and tear properties, good resistance to ozone ozone (ō`zōn), an allotropic form of the chemical element oxygen (see allotropy). Pure ozone is an unstable, faintly bluish gas with a characteristic fresh, penetrating odor. The gas has a density of 2.144 grams per liter at STP. and oxygen, and good low temperature properties. Solid, or millable, urethanes are a form of urethanes that are processable on conventional rubber machinery and compounded much in the same way as other commonly used rubbers. Blends of rubbers are fairly common in rubber compounding because of two factors: the ability to improve the properties of one rubber by the addition of a second, and the ability to lower the cost of the more expensive rubber by blending with a less expensive rubber, and hopefully keeping most of the benefits of the costlier rubber. This article studies blends of several types of solid urethane rubber with several more common polymers. The bulk of the study is with blends of urethane with NBR NBR Number NBR Nightly Business Report (PBS show) NBR National Business Review (New Zealand weekly business newspaper) NBR National Bureau of Asian Research NBR National Board of Review , although examples of blends with other polymer are given. Experimental Identification of all ingredients used is found in table 1. Formulations used are shown in tables 2-9.
Table 1 - ingredients
Ingredients Description Supplier
used
6PPD N-phenyl-N'-cyclohexyl-p- Uniroyal Chemical
phenylene-diamine
AU-1 Polyester urethane rubber Uniroyal Chemical
AU-2 Polyester urethane rubber Uniroyal Chemical
C-4 Zinc chloride-MBTS complex Uniroyal Chemical
CDMC Copper dimethyl dithiocarbamate R.T. Vanderbilt
DBEEA Di (butoxy-ethoxy-ethyl) Morton International
adipate
DBEEF Di (butoxy-ethoxy-ethyl) formal Morton International
DCP40 Dicumyl peroxide, 40% Hercules Inc.
EPDM-1 EPDM, 60 ML/125C, 62/38 E/P Uniroyal Chemical
EU-1 Polyether urethane rubber, Uniroyal Chemical
milled
EU-2 Polyether urethane rubber, Uniroyal Chemical
unmilled
HNBR Hydrogenated nitrile rubber Bayer
NBR-40 Acrylonitrile rubber, medium Uniroyal Chemical
ACN, 40 ML/100 [degrees] C
NBR-50 Acrylonitrile rubber, medium Uniroyal Chemical
ACN, 50 ML/100 [degrees] C
NBR/PVC Nitrile rubber/PVC, 70/30 Uniroyal Chemical
Precipita- Precipitated silica PPG Industries
ted silica
Proc. aid 1 Process aid Struktol Co.
TMTD Tetramethyl thiuram disulfide Uniroyal Chemical
TMPTMA Trimethylol propane Sartomer Company
trimethacrylate
TMQ Polymerized 1,2-dihydro-2,2,4 Uniroyal Chemical
tri-methylquinoline
Wax Blend of waxes Uniroyal Chemical
Table 2 - AU-1/NBR40 blends
A B C D E
AU-1 100 75 50 25 --
NBR40 -- 25 50 75 100
N330 Black 30 30 30 30 30
DBEEA 5 5 5 5 5
Zinc stearate 0.5 0.5 0.5 0.5 --
Stearicacid -- -- -- -- 1
Proc. aid 1 1 1 1 1 1
TMQ -- 0.5 1 1.5 2
6PPD -- 0.5 1 1.5 2
Wax -- 0.5 1 1.5 2
MBTS 4 4 4 4 2
MBT 2 2 2 2 --
C-4 1 1 1 1 --
Sulfur 1.5 1.5 1.5 1.5 1.5
TMTD -- -- -- -- 1
DCP40 -- -- -- -- --
Zinc oxide -- -- -- -- 5
145 146.5 148 149.5 146.5
F G H I J
AU-1 100 75 50 25 --
NBR40 -- 25 50 75 100
N330 Black 30 30 30 30 30
DBEEA 5 5 5 5 5
Zinc stearate -- -- -- -- --
Stearicacid 0.25 0.25 0.25 0.25 0.25
Proc. aid 1 1 1 1 1 1
TMQ -- 0.5 1 1.5 2
6PPD -- 0.5 1 1.5 2
Wax -- 0.5 1 1.5 2
MBTS -- -- -- -- --
MBT -- -- -- -- --
C-4 -- -- -- -- --
Sulfur -- -- -- -- --
TMTD -- -- -- -- --
DCP40 1.5 2 2.5 3 3.5
Zinc oxide -- -- -- -- --
137.75 139.75 141.75 143.75 145.75
Table 3 - AU-1/NBR 40 blends
A B C D
AU-1 100 75 50 25
NBR 40 -- 25 50 75
Sulfur cure
Mooney viscosity, ML/100
[degrees] C 30 30 30 30
Mooney scorch, ML/125
[degrees] C
Minimum 16 18 18 19
t5, minutes 15 10 10 11
Curemeter 30'/160
[degrees] C, 1 [degrees]
arc, 1.7 Hz
ML, dN-m 2.1 3.7 3.8 3.8
MH, dN-m 57.5 37.9 32.4 29.3
ts1, min. 2.8 1.7 1.6 1.7
tc50, min. 5.1 2.9 2.6 2.6
tc90, min. 7.1 3.9 3.6 3.8
Reversion, dN-m 8.4 12.5 6.5 2.4
Cured physical properties
Press cure, min./160
[degrees] C 9 5 5 5
At RT (23 [degrees] C)
Hardness, Shore A 72 73 68 61
100% modulus, MPa 3.6 4.0 2.2 1.7
300% modulus, MPa 13.2 10.6 8.1 4.9
Tensile strength, MPa 38.7 21.7 17.2 20.8
Elongation, % 650 570 560 770
Tear, Die C, N/mm 52.1 42.4 35.4 34.8
Bashore rebound, % 11 9 11 12
At 75 [degrees] C
300% modulus, MPa 9.1 7.2 5.8 4.1
Tensile strength, MPa 15.0 12.5 8.9 8.3
% change -61 -42 -48 -60
Elongation, % 520 510 435 500
Tear, die C, lb./in. 36.2 28.0 18.6 18.4
% change -30 -34 -48 -47
At 100 [degrees] C
300% modulus, MPa 10.6 7.8 6.7 4.5
Tensile strength, MPa 14.6 11.0 7.4 6.1
% change -62 -49 -57 -70
Elongation, % 425 410 318 370
Tear, Die C, lb/in 24.5 22.8 13.6 11.7
% change -53 -46 -62 -66
Oven aged, 70 hrs./125
[degrees] C
Hardness, Shore A 77 88 78 72
Change 6 15 11 11
300% modulus, MPa 18.7
% change 42
Tensile strength, MPa 25.6 16.6 13.5 16.5
% change -34 -24 -22 -21
Elongation, % 430 230 205 270
% change -34 -60 -63 -65
TEf 0.44 0.31 0.29 0.28
Aged in ASTM 903 oil, 70
hrs./100 [degrees] C
Hardness, Shore A 70 65 57 52
Change -2 -8 -11 -9
300% modulus, MPa 20.1 13.8 7.9
% change 53 30 62
Tensile strength, MPa 27.4 14.0 10.7 11.2
% change -29 -35 -38 -46
Elongation, % 393 305 290 380
% Change -40 -46 -48 -51
Volume change, % -2 0 2 4
Compression set
22 hrs./70 [degrees] C 36 33 29 24
22 13rs./100 [degrees] C 86 75 60 53
Brittle point, [degrees]
C -31 -30 -29 -30
E F G
AU-1 -- 100 75
NBR 40 100 -- 25
Peroxide cure
Mooney viscosity, ML/100
[degrees] C 32 31 34
Mooney scorch, ML/125
[degrees] C
Minimum 21 15 20
t5, minutes 9 32 31
Curemeter 30'/160
[degrees] C, 1 [degrees]
arc, 1.7 Hz
ML, dN-m 3.7 1.9 3.3
MH, dN-m 40.6 28.2 20.5
ts1, min. 1.6 1.9 2.2
tc50, min. 2.1 6.2 6.7
tc90, min. 2.7 13.5 14.4
Reversion, dN-m 0.5 0.9 0.5
Cured physical properties
Press cure, min./160
[degrees] C 5 20 20
At RT (23 [degrees] C)
Hardness, Shore A 58 66 65
100% modulus, MPa 1.7 1.9 1.5
300% modulus, MPa 7.1 8.3 4.6
Tensile strength, MPa 16.9 26.5 21.6
Elongation, % 510 720 850
Tear, Die C, N/mm 35.2 33.1 31.9
Bashore rebound, % 15 18 16
At 75 [degrees] C
300% modulus, MPa 5.9 4.4 4.1
Tensile strength, MPa 5.9 11.8 8.6
% change -65 -55 -60
Elongation, % 240 650 590
Tear, die C, lb./in. 14.4 25.7 20.3
% change -59 -22 -36
At 100 [degrees] C
300% modulus, MPa 5.4 3.9
Tensile strength, MPa 47 11.0 8.6
% change -72 -58 -60
Elongation, % 220 530 570
Tear, Die C, lb/in 10.7 17.5 14.9
% change -70 -47 -53
Oven aged, 70 hrs./125
[degrees] C
Hardness, Shore A 71 70 73
Change 13 4 8
300% modulus, MPa 9.4 10.9
% change 13 139
Tensile strength, MPa 12.2 23.2 18.0
% change -28 -12 -17
Elongation, % 230 550 510
% change -55 -24 -40
TEf 0.33 0.67 0.50
Aged in ASTM 903 oil, 70
hrs./100 [degrees] C
Hardness, Shore A 50 60 52
Change -8 -6 -13
300% modulus, MPa 10.2 5.6
% change 23 23
Tensile strength, MPa 6.6 17.1 8.1
% change -61 -35 -62
Elongation, % 230 435 395
% Change -55 -40 -54
Volume change, % 7 -1 2
Compression set
22 hrs./70 [degrees] C 11 18 20
22 13rs./100 [degrees] C 26 32 28
Brittle point, [degrees]
C -34 -48 -55
H I J
AU-1 50 25 --
NBR 40 50 75 100
Peroxide cure
Mooney viscosity, ML/100
[degrees] C 34 35 35
Mooney scorch, ML/125
[degrees] C
Minimum 20 23 23
t5, minutes 40 50 50
Curemeter 30'/160
[degrees] C, 1 [degrees]
arc, 1.7 Hz
ML, dN-m 3.6 38.0 3.6
MH, dN-m 18.7 18.3 17.7
ts1, min. 2.5 2.6 3.0
tc50, min. 7.5 8.6 9.4
tc90, min. 16.2 19.3 20.9
Reversion, dN-m 0.0 0.0 0.0
Cured physical properties
Press cure, min./160
[degrees] C 20 20 25
At RT (23 [degrees] C)
Hardness, Shore A 61 56 54
100% modulus, MPa 1.2 1.0 1.0
300% modulus, MPa 3.5 2.6 2.3
Tensile strength, MPa 19.1 17.1 18.3
Elongation, % 905 990 1,055
Tear, Die C, N/mm 29.3 28.5 31.8
Bashore rebound, % 18 21 25
At 75 [degrees] C
300% modulus, MPa 3.8 2.3 2.2
Tensile strength, MPa 8.3 7.2 6.2
% change -57 -58 -66
Elongation, % 585 580 555
Tear, die C, lb./in. 17.3 14.9 15.8
% change -41 -48 -50
At 100 [degrees] C
300% modulus, MPa 3.3 2.5 2.1
Tensile strength, MPa 7.3 5.9 7.3
% change -62 -65 -60
Elongation, % 505 500 550
Tear, Die C, lb/in 11.0 9.8 10.9
% change -62 -66 -66
Oven aged, 70 hrs./125
[degrees] C
Hardness, Shore A 70 68 68
Change 10 12 14
300% modulus, MPa 10.2 8.4 8.3
% change 194 230 253
Tensile strength, MPa 17.2 18.0 20.2
% change -10 5 11
Elongation, % 470 530 565
% change -48 -46 -46
TEf 0.47 0.56 0.59
Aged in ASTM 903 oil, 70
hrs./100 [degrees] C
Hardness, Shore A 45 44 35
Change -16 -12 -19
300% modulus, MPa 4.4 3.5 2.6
% change 28 38 10
Tensile strength, MPa 8.8 7.9 8.6
% change -54 -54 -53
Elongation, % 455 480 570
% Change -50 -52 -46
Volume change, % 4 8 9
Compression set
22 hrs./70 [degrees] C 20 16 21
22 13rs./100 [degrees] C 23 18 23
Brittle point, [degrees]
C -52 -47 -52
Table 4 - AU-1/NBR50 blends
Polyester urethane AU-2 100 75 50 25 0
NBR-50 0 25 50 75 100
Stearic acid 0.25 0.25 0.25 0.25 0.25
N330 black 35 35 35 35 35
TP90B 5 5 5 5 5
DiCup 40C 4 4 4 4 4
Taber abrasion, 5,000
cycles
g lost 0.033 0.051 0.044 0.082 0.034
Press cure 35'/160
[degrees] C
Hardness, Shore A 72 68 68 66 66
100% modulus, MPa 4.9 5 4.5 4 3.8
200% modulus, MPa 11.9 11.5 12.6 13.5 13.5
Tensile strength, MPa 24.6 15.4 14.3 15.8 18.8
Elongation, % 530 330 230 220 250
Tear C, N/mm 81 44 28 31 31
Oven aged 70 hrs./149
[degrees] C
Hardness change, points 10 23 21 23 20
Tensile change, % -6 -12 -48 -70 -78
Elongation change, % -55 -88 -100 -100 -100
Aged 7 days Fuel B at RT
Hardness change, points -7 -8 -9 -7 -8
Tensile change, % -13 -20 -35 -49 -54
Elongation change, % -19 -36 -48 -50 -48
Volume change, % 10.1 15.3 20.6 24.1 28.2
Aged 70 hrs./121 [degrees]
C ASTM #1 oil
Hardness change, points 9 -4 0 1 0
Tensile change, % -36 -39 -23 -16 -20
Elongation change, % -17 -48 -39 -32 -36
Volume change, % -4.7 -4.6 -3.8 -39 -3.5
Compression set, %
22 hrs./70 [degrees] C 27 31 14 7 6
22 hrs./100 [degrees] C 43 34 16 9 8
Brittle point -43 -38 -38 -43 -43
Table 5 - AU-1/SBR blends
AU-1 100 80 70 50 0
SBR 0 20 30 50 100
N330 black 30 30 30 30 30
Zinc stearate 0.5 0.5 0.5 0.5 --
MBTS 4 4 4 4 1
MBT 1 1 1 1 --
C-4 1 1 1 1 --
Sulfur 1.5 1.5 1.5 1.5 2
Stearic acid
Zinc oxide -- -- -- 5
CDMC -- -- -- 0.35
Press cure, 20'/149
[degrees] C
Hardness, Shore A 78 77 75 72 60
200% modulus, Mpa 11.3 10.3 10.8 6.6 6.1
Tensile strength, Mpa 30.0 25.9 24.8 20.1 10.7
Elongation, % 460 440 430 460 270
Tear die C, N/mm 70.0 63.0 66.5 59.5 33.3
Taber abrasion, grams loss
5,000 cycles 0.039 0.102 0.099 0.184 0.070
Table 6 - Eu-1/BR blends
A B C D
Polyether urethane EU-1 100 75 50 25
Cis-4 BR 25 50 75
Other ingredients: N220-30; MBTS-4; MBT-2; Caytur 4-1;
zinc stearate-0.5; sulfur-1.5
Press cure, 30'/154
[degrees] C
Hardness, Shore A 77 75 75 73
100% modulus, MPa 4.6 4.3 4.3 3.8
Tensile strength, MPa 32.9 24.1 21.5 16.9
Elongation, % 380 350 330 340
Tear Die C, N/mm 49 48 40 34
Compression set
22 hrs./70 [degrees] C 22 21 23 20
Taber abrasion, grams loss
5,000 cycles 0.033 0.088 0.109 3.116
Volume swell, % 7 days/23 [degrees] C (room temperature)
Water 4.3 3.7 3.4 2.7
Toluene 141 152 167 186
MEK 126 112 102 82
Ethylene glycol 2.7 2.4 1.8 1.2
Acetic acid 184 137 130 82
Ethyl acetate 109 103 99 82
Table 7 - AU-1/EPDM-1 blends
A B C D E
AU-1 100 80 70 50 0
EPDM-1 0 20 30 50 100
N330 black 30 30 30 30 30
Zinc stearate 0.5 0.5 0.5 0.5 --
MBTS 4 4 4 4 --
MBT 1 1 1 1 --
C-4 1 1 1 1 --
Sulfur 1.5 1.5 1.5 1.5 1
Stearic acid -- -- -- -- 1
Zinc oxide -- -- -- -- 5
TMTM -- -- -- -- 1
Press cure, 20'/149 [degrees] C
Hardness, Shore A 83 80 80 79 62
200% modulus, MPa 16.3 13.3 10.3 5.9 4.6
Tensile strength, MPa 32.8 24.1 15.2 6.2 20.7
Elongation, % 410 400 330 220 460
Tear Die C, N/mm 73.5 59.5 50.8 31.5 38.5
Taber abrasion, grams loss
5,000 cycles 0.04 0.23 0.66 0.84 0.12
Table 8 - EU-2/NBR/PVC blends
A B C D E
EU-2 100 50 50 10 0
NBR/PVC 0 50 50 90 100
Stearic acid -- -- 1 -- 1
Zinc oxide -- -- 5 -- 5
Precipitated silica 40 40 40 40 40
MBTS 4 4 1 1 1
MBT 1 1 -- -- --
C4 0.4 0.4 -- -- --
Sulfur 0.75 0.75 1.5 1.5 1.5
Cadmium stearate 0.5 0.5 -- -- --
Press cure 60'/142
[degrees] C
Hardness, Shore A 78 84 85 88 88
300% modulus, MPa 11.7 10.3 6.9 6.8 8.5
Tensile strength, MPa 31.0 25.2 19.0 13.1 12.6
Elongation, % 500 540 710 700 540
Brittle point, [degrees] C -65 -59 -64 -38 -33
NBS abrasion index 324 113 158 76 85
Aged 70 hours/100 [degrees] C ASTM #3 oil
Hardness change, points -9 -8 -13 -17 -14
Tensile change, % -10 -23 15 24 -22
Elongation change, % -4 -9 -21 -7 -2
Volume change, % 0 19 22 22 21
Table 9 - AU-2/HNBR blends
A B C
Polyester urethane AU-2 100 50 0
HNBR 0 50 100
N330 black 30 30 30
Stearic acid 0.25 0.25 0.25
TMPTMA 5 5 5
DCP40 5 5 5
Press cure, 15'/171 [degrees] C
Hardness, Shore A 85 75 72
100% modulus, MPa 8.0 4.2 3.0
Tensile strength, MPa 30.2 25.9 26.8
Elongation, % 280 410 450
Tear die C, N/mm 45.5 38.5 35.0
Brittle point, C -45 -59 <-70
NBS abrasion index 627 375 638
Aged 70 hours/RT fuel C
Hardness change, points -15 -25 -37
Tensile change, % -32 -56 -81
Elongation change, % -21 -49 -62
Volume change, % 24 51 77
Aged 70 hours/150 [degrees]
C ASTM #3 oil
Hardness change, points -33 -20 -19
Tensile change, % -83 -56 -21
Elongation change, % -11 -34 -9
Volume change, % 6 17 28
Aged 70 hours/150 [degrees]
C air oven
Hardness change, points -3 4 3
Tensile change, % -48 -34 -5
Elongation change, % -25 -49 -27
Compression set 70 hrs/125
[degrees] C, % 88 63 39
Compounds were mixed in a laboratory internal mixer mixer, either of two electronic devices in which two or more signals are combined. In the type of mixer used in radio receivers, radar receivers, and similar systems, a signal is translated upward or downward in frequency. with the following mix procedure: * Rotor speed - 75 RPM (1) (Revolutions Per Minute) With electric and electronics devices, RPM measures the rotational speed of the motor's spindle. Floppy disks rotate at 300 RPM, while hard disks rotate from 3,000 to 15,000 RPM. , temperature of mixer (rotors, sides, door) was 23 [degrees] C; * Load polymers and zinc stearate Zinc stearate (Zn(C18H35O2)2) is a chemical compound. Zinc stearate is a zinc soap that repels water. It is insoluble in polar solvents such as alcohol and ether but soluble in aromatic hydrocarbons eg benzene and chlorinated hydrocarbons or stearic acid stearic acid /ste·a·ric ac·id/ (ste-ar´ik) a saturated 18-carbon fatty acid occurring in most fats and oils, particularly of tropical plants and land animals; used pharmaceutically as a tablet and capsule lubricant and as an emulsifying ; * Ram down Verb 1. ram down - strike or drive against with a heavy impact; "ram the gate with a sledgehammer"; "pound on the door" ram, pound thrust - push forcefully; "He thrust his chin forward" 2. , clock to 0'; * At 1', add black, plasticizer plas·ti·ciz·er n. Any of various substances added to plastics or other materials to make or keep them soft or pliable. plasticizer or -ciser Noun and other ingredients, ram down; * At 2.0', sweep; * At 3.5', dump; * Curatives were added to stocks in a second step on a cool mill. Compounds were cured and tested to ASTM ASTM abbr. American Society for Testing and Materials procedures. Compounds were press cured at 160 [degrees] C, with the cure times approximately the curemeter t90 plus two minutes. Samples for Bashore resilience resilience (r  ·zilˑ·yens),n and compression set tests, 12.7 mm in thickness thickness (thik´nes) a measurement across the smallest dimension of an object. triceps skinfold (TSF) thickness , were cured for 2x the standard press cure time. Abrasion resistance tests used in the studies were: * Pico abrasion (ASTM D2228) - this test determines abrasion resistance by measuring the volume loss of samples abraded by tungsten carbide tungsten carbide n. An extremely hard, fine gray powder whose composition is WC, used in tools, dies, wear-resistant machine parts, and abrasives. knives knives n. Plural of knife. knives Noun the plural of knife knives knife compared to reference compounds. * DIN abrasion (ASTM D5963) - this test determines abrasion resistance by measuring the volume loss of samples sliding across the surface of an abrasive abrasive, material used to grind, smooth, cut, or polish another substance. Natural abrasives include sand, pumice, corundum, and ground quartz. Carborundum (silicon carbide) and alumina (aluminum oxide) are important synthetically produced abrasives. sheet attached to a rotating ro·tate v. ro·tat·ed, ro·tat·ing, ro·tates v.intr. 1. To turn around on an axis or center. 2. dram dram: see English units of measurement. See dynamic RAM. DRAM - dynamic random-access memory , comparing the results to that of a standard rubber. Samples were tested using a rotating test specimen SPECIMEN. A sample; a part of something by which the other may be known. 2. The act of congress of July 4, 1836, section 6, requires the inventor or discoverer of an invention or discovery to accompany his petition and specification for a patent with specimens . * Taber Taber (tā`bər), town (1991 pop. 6,660), S Alta., Canada, NE of Lethbridge. The area is irrigated for crop and livestock raising. The town has a sugar beet refinery and a vegetable cannery. Coal, oil, and natural gas are found nearby. abrasion (ASTM D4060) - this test evaluates the resistance of a material to abrasive wear by the contact of a test sample, turning on a vertical axis, against the sliding rotation Rotation An active asset management strategy that tactically overweighted and underweighted certain sectors, depending on expected performance. Sometimes called sector rotation. of two abrading wheels. The wheels are driven by the sample in opposite directions about a horizontal axis displaced displaced see displacement. tangentially tan·gen·tial also tan·gen·tal adj. 1. Of, relating to, or moving along or in the direction of a tangent. 2. Merely touching or slightly connected. 3. from the axis of the the diameter of the sphere which is perpendicular to the plane of the circle. See also: Axis sample. The H-22 wheel was used with a 1,000 gram load. Results and discussion Polyester polyester, synthetic fiber, produced by the polymerization of the product formed when an alcohol and organic acid react. The outstanding characteristic of polyesters is their ability to resist wrinkling and to spring back into shape when creased. urethane 1/NBR-40 blends A polyester urethane (ASTM designation DESIGNATION, wills. The expression used by a testator, instead of the name of the person or the thing he is desirous to name; for example, a legacy to. the eldest son of such a person, would be a designation of the legatee. Vide 1 Rop. Leg. ch. 2. 2. AU, Mooney Mooney is family name, which is probably predominantly derived from the Irish Ó Maonaigh. It can also be spelled Moony, Meaney, Mauney, Moon, Money. The word can refer to: Companies
Meaney spelling ACN Accenture ACN Australian Company Number ACN Automatic Collision Notification (US DOT) ACN Acetonitrile ACN Anglican Communion Network NBR with Mooney viscosity ML (1+4)/100 [degrees] C of 40, designated NBR40, were chosen for the main part of this study. Blends from 100/0 to 0/100 of the polymers, in 25% increments, were evaluated in both sulfur sulfur or sulphur (sŭl`fər), nonmetallic chemical element; symbol S; at. no. 16; at. wt. 32.06; m.p. 112.8°C; (rhombic), 119.0°C; (monoclinic), about 120°C; (amorphous); b.p. 444.674°C;; sp. gr. at 20°C;, 2. and peroxide peroxide (pərŏk`sīd), chemical compound containing two oxygen atoms, each of which is bonded to the other and to a radical or some element other than oxygen; e.g. cure systems. The formulas used are shown in table 2. The formulation formulation /for·mu·la·tion/ (for?mu-la´shun) the act or product of formulating. American Law Institute Formulation used was polymer rich, as is typical with urethanes, having 30 parts of a reinforcing black and 5 parts of plasticizer. The sulfur cure system used for the AU-1 and AU-1/NBR40 blends is a common cure system used with solid urethanes. It contains MBTS MBTS 2-Mercaptobenzothiazyl Disulfide MBTS Missile Bit Test Set MBTS Missile Bench Test Set , MBT MBT Minimum (Spark Advance For) Best Torque MBT Masai Barefoot Technology MBT Main Battle Tank MBT Mechanical Biological Treatment (waste treatment) MBT Mercaptobenzothiazole MBT Master of Business Taxation and a reaction product of zinc chloride zinc chloride n. A white, water-soluble crystalline compound, ZnCl2, used as a wood preservative, as a soldering flux, and for a variety of industrial purposes, including the manufacture of cements and paper parchment. with MBTS along with sulfur. The 100% NBR40 compound used a typical cure system for that polymer based upon MBTS, TMTD TMTD tetramethylthiuram disulfide. and sulfur. The 100% NBR compound also used a common antidegradant combination (6PPD (1) (Parallel Presence Detect) The method used by earlier SIMM memory modules to communicate their capacity to the computer. A binary number coming from a parallel set of pins was read by the system, with each pin representing one bit. Contrast with SPD. , TMQ TMQ Terminal-Port Queueing (Cisco) TMQ Talking Message Queue and wax) and the blends with AU used a proportional proportional values expressed as a proportion of the total number of values in a series. proportional dwarf the patient is a miniature without disproportionate reductions or enlargements of body parts. amount of these ingredients, keeping the same parts per 100 parts of NBR40 level. For the peroxide cures, dicumyl peroxide, 40% active, was used at the 1.5 phr level for AU-1, 3.5 phr level for NBR-40 and intermediate levels for the blends. The data, shown in table 3, show the following: * Curemeter data: With both the sulfur and peroxide cures, as the level of NBR40 increases, the maximum torque (MH) value decreases. With the sulfur cure, the scorch times and the cure times shorten (audio, compression) Shorten - A form of lossless audio compression. as the NBR40 level increases, while with the peroxide cure, the scorch and cure times lengthen length·en tr. & intr.v. length·ened, length·en·ing, length·ens To make or become longer. length  en·er n. slightly. Also of note is the fact that the reversion reversion: see atavism. tendency of the urethanes, especially with sulfur cures, is reduced
considerably with the addition of NBR. This can be of benefit for long
cures necessary with thick cross-section cross section also cross-sec·tionn. 1. a. A section formed by a plane cutting through an object, usually at right angles to an axis. b. A piece so cut or a graphic representation of such a piece. 2. parts. * Hardness, modulus See modulo. , tensile strength tensile strength Ratio of the maximum load a material can support without fracture when being stretched to the original area of a cross section of the material. When stresses less than the tensile strength are removed, a material completely or partially returns to its and elongation elongation, in astronomy, the angular distance between two points in the sky as measured from a third point. The elongation of a planet is usually measured as the angular distance from the sun to the planet as measured from the earth. : The unaged cured properties showed a reduction in hardness, modulus, tensile strength and tear strength as NBR40 is added to AU-1 (figure 1). Most of the drop-off in properties occurs between the 100/0 and 75/25 AU/NBR blends, with the values somewhat leveling off toward the 100% NBR mark. [GRAPH OMITTED] Physical properties of rubber, measured at elevated temperatures, are typically significantly lower than those properties at room temperature. The tensile strength of AU-1 and NBR40 shows a reduction at 75 [degrees] C and 100 [degrees] C, but the percent reduction at elevated temperatures is lower for the blends vs. the neat polymers, as shown in figure 2. The percent reduction in tear strength at elevated temperatures is fairly linear, with the least reduction with 100% AU-1 and the most with NBR40. This suggests that a partial substitution Substitution Arsinoë put her own son in place of Orestes; her son was killed and Orestes was saved. [Gk. Myth.: Zimmerman, 32] Barabbas robber freed in Christ’s stead. [N.T.: Matthew 27:15–18; Swed. Lit. of AU-1 in an NBR compound can result in improved hot tear properties, and hence be a benefit in demolding intricate cross sections. [GRAPH OMITTED] * Compression set: In the sulfur cures, NBR40 was significantly better for compression set than AU-1, with intermediate blends giving fairly linear values between the two. With the peroxide cures, the less severe conditions of 22 hrs./70 [degrees] C show little difference between the polymer blends A polymer blend, polymer alloy, or polymer mixture is a member of a class of materials analogous to metal alloys, in which two or more polymers are blended together to create a new material with different physical properties. , but the more stringent conditions of 22 hrs./100 [degrees] C show the same trend as the sulfur cures (figure 3). [GRAPH OMITTED] * Oven  It has been suggested that , , , , and be merged into this article or section. and oil agings: Compounds were oven-aged 22 hrs./70
[degrees] C, 70 hrs./100 [degrees] C and 70 hrs./125 [degrees] C. The
data in table 3 shows the 100% AU-1 compound to be slightly better than
the NBR40 and blends, but the overall differences are not that
significant. The NBR40, with its TMQ/6PPD/wax antidegradant package,
stood up well to the oven agings, almost as well as the AU-1 without
anti-degradant. The aging in ASTM 903 oil, 70 hrs./100 [degrees] C,
showed the AU-1 to have better retention of properties and volume change
than the NBR40 compound and intermediate blends. The volume change,
shown in figure 4, showed the AU-1 compound losing about 1% volume,
possibly because of some plasticizer extraction extraction /ex·trac·tion/ (eks-trak´shun)1. the process or act of pulling or drawing out. 2. the preparation of an extract. . The NBR40 compound and intermediate blends show the linear relationship of higher swell with higher NBR40 levels. This suggests that even a small substitution of AU-1 for NBR40 can have a beneficial effect on oil resistance properties. [GRAPH OMITTED] * Abrasion resistance: Pico and DIN abrasion tests show the superiority of urethane AU-1 vs. NBR. Both tests showed the 100% AU-1 compound to have significantly higher abrasion resistance than the blends, with the majority of the difference coming between 100/0 and 75/25 AU1/NBR40 (figure 5). Generally, adding up to 50% AU-1 to the blend with NBR40 gave about a 10-20% improvement in abrasion resistance with the two tests. [GRAPH OMITTED] * Other tests: Brittle (jargon) brittle - Said of software that is functional but easily broken by changes in operating environment or configuration, or by any minor tweak to the software itself. Also, any system that responds inappropriately and disastrously to abnormal but expected external stimuli; e. point data showed little significant differences between the blends, with the peroxide cure giving overall better (lower) brittle points than the sulfur cures. Ozone resistance, tested for 670 hours at 40 [degrees] C with 50% strain at 50 pphm ozone concentration, indicated no signs of cracking cracking - cracker with any of the compounds. Polyester urethane 2/NBR-50 blends Blends of a polyester urethane rubber (AU-2, ML/100 [degrees] C of 60) with a 50 ML/100 [degrees] C medium ACN NBR (NBR-50) were evaluated in a peroxide cure. The compound is similar to that in the above examples and is shown in table 4 along with the test data. This urethane rubber has a higher optimum level of peroxide and, hence, the level of peroxide used in the blends and the solo polymers was the same, 4 phr. Physical properties show a valley in the tensile strength curve, where the neat polymers gave higher tensiles than the blends (figure 6). The Taber abrasion resistance index showed a similar trend, with the best abrasion resistance being with the neat polymers, although the 25 and 50% substitutions of NBR50 showed only a gradual The Gradual (Latin: graduale, sometimes called the Grail) is a chant in the extraordinary form of the Roman Catholic Mass, sung after the reading or singing of the Epistle and before the Alleluia, or, during penitential seasons, before the Tract. decrease in abrasion resistance. [GRAPH OMITTED] Aging in Fuel B at room temperature for seven days showed the AU-2 compound to have lower volume change and less change in properties than the NBR50 compound and intermediate blends (figure 7). The results were essentially linear, indicating that any substitution of AU-2 for NBR50 would give better resistance to Fuel B. Results for aging in ASTM #1 oil for 70 hrs./121 [degrees] C showed similar volume changes for all the polymer blends, but reduced hardness and tensile changes as the NBR50 level is increased. Compression set values, as with AU-1/NBR40 blends, showed better (lower) set as the % NBR was increased in the blend. [GRAPH OMITTED] Polyester urethane 1/SBR blends SBR SBR - Spectral Band Replication 1500 was blended with AU-1 in ratios from 100/0 to 50/50 AU-1/SBR, with a 100% SBR compound as a control. The data showed slight to moderate reduction in physical properties as the % of SBR was increased (table 5); however, the Taber abrasion data showed that all the intermediate blends were significantly poorer than 100% AU-1 or SBR 1500. Blends with SBR would be beneficial if the goal was to improve the oil or ozone resistance or physical properties of the SBR by adding a portion of urethane rubber to the blend. If abrasion resistance is a significant factor, AU1/SBR blends in this study did not offer any advantage over the polymers themselves. Polyether pol·y·e·ther n. A polymer in which the repeating unit contains two carbon atoms linked by an oxygen atom. urethane 1/BR blends Cis-4 butadiene butadiene (by  t'ədī`ēn), colorless, gaseous hydrocarbon. There are two structural isomers of butadiene; they differ in the location of the two carbon-carbon double bonds in the rubber (BR-1) was blended up to 75 parts with a
polyether urethane EU-1 to evaluate properties. The formulation and data
are shown in table 6. Generally, the physical properties diminished di·min·ish v. di·min·ished, di·min·ish·ing, di·min·ish·es v.tr. 1. a. To make smaller or less or to cause to appear so. b. linearly with the amount of BR-1 in the blend or, conversely con·verse 1 intr.v. con·versed, con·vers·ing, con·vers·es 1. To engage in a spoken exchange of thoughts, ideas, or feelings; talk. See Synonyms at speak. 2. , improved with increasing amounts of EU-1 in the blend. Tensile strength and Taber abrasion data are shown in figure 8. Resistance to several solvents and chemicals was evaluated, all testing the volume change after seven days at room temperature exposure. The data showed that water, ethylene glycol ethylene glycol: see glycol. ethylene glycol Simplest member of the glycol family, also called 1,2-ethanediol (HOCH2CH2OH). It is a colourless, oily liquid with a mild odour and sweet taste. , MEK Noun 1. MEK - a terrorist organization formed in the 1960s by children of Iranian merchants; sought to counter the Shah of Iran's pro-western policies of modernization and opposition to communism; following a philosophy that mixes Marxism and Islam it now attacks the , ethyl acetate ethyl acetate n. A colorless volatile flammable liquid, CH3COOC2H5, used in perfumes, flavorings, lacquers, pharmaceuticals, and rayon and as a general solvent. and acetic acid acetic acid (əsē`tĭk), CH3CO2H, colorless liquid that has a characteristic pungent odor, boils at 118°C;, and is miscible with water in all proportions; it is a weak organic carboxylic acid (see carboxyl group). resistance improved with increasing BR content, while toluene toluene (tōl`y ēn') or methylbenzene (mĕth'əlbĕn`zēn), C7H8 resistance improved with increasing
EU-1 content. Although urethanes are generally good for oils and
petroleum solvents, their solvent solvent, constituent of a solution that acts as a dissolving agent. In solutions of solids or gases in a liquid, the liquid is the solvent. In all other solutions (i.e. and chemical resistance to other
materials can often be improved by the combination with other polymers.[GRAPH OMITTED] Polyester urethane/EPDM blends Polyester urethane AU-1 was blended with an EPDM rubber EPDM rubber (ethylene propylene diene monomer rubber) is an elastomer which is characterized by wide range of applications. EPDM rubber is used in vibrators and seals; glass-run channel; radiator, garden and appliance hose; tubing; washers; belts; and electrical insulation. (EPDM-1, 60 ML/125 [degrees] C, 63/37E/P ratio E/P ratio See earnings-price ratio (E/P ratio). , medium ENB) at levels up to 50% EPDM EPDM Ethylene-Propylene-Diene-Monomer EPDM Enterprise Product Data Management EPDM Ethylene Propylene Dimonomer (industrial/commercial piping/plumbing components) EPDM Engineering Product Data Management with a 100% EPDM control. The data (table 7) indicate that the physical properties are significantly affected by even a 20% substitution of EPDM for the urethane. The property most affected is the abrasion resistance, which showed poorer abrasion resistance for the 80/20 to 50/50 blends than either the 100% AU-1 or the EPDM-1 compounds. Because of the EPDM' s low polarity (1) The direction of charged particles, which may determine the binary status of a bit. (2) In micrographics, the change in the light to dark relationship of an image when copies are made. , blends of it with the highly polar urethane rubber may not be feasible (algorithm) feasible - A description of an algorithm that takes polynomial time (that is, for a problem set of size N, the resources required to solve the problem can be expressed as some polynomial involving N). without a compatibilizer to improve the blends of these polymers. Polyether urethane/NBR/PVC blends A commercial NBR/PVC (70/30) blend was evaluated in blends with a polyether urethane (EU-2) similar to EU-1, at blend ratios of 90/10 and 50/50, along with 100% NBR/PVC and EU-1 compounds. The data (table 8) indicate the benefit to tensile strength of adding even small amounts of EU-2 to the NBR/PVC. The EU-2 urethane also significantly improves the low temperature properties as shown by the brittle point improvement (figure 9). The data show two different cure systems for 50/50 compounds. The standard urethane cure system (with MBTS, MBT, C-4 and sulfur) gave better tensile strength but lower NBS (National Bureau of Standards) See NIST. NBS - National Bureau of Standards: part of the US Department of Commerce, now NIST. abrasion than the cure system used with the 100% NBR/PVC (MBTS, sulfur, zinc oxide zinc oxide, chemical compound, ZnO, that is nearly insoluble in water but soluble in acids or alkalies. It occurs as white hexagonal crystals or a white powder commonly known as zinc white. and stearic acid). [GRAPH OMITTED] Polyester urethane/HNBR blends A 50/50 blend of a highly hydrogenated nitrile rubber Nitrile rubber, or Buna-N,is a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene. Some trade names are: Nipol, Krynac and Europrene. (HNBR HNBR Hydrogenated Acrylonitrile-Butadiene Rubber ) with polyester urethane AU-2 was compared to compounds of the 100% polymers. Physical properties were tested on the original cures and after oven, oil and fuel agings. The data in table 9 show the urethane to give a harder compound with slightly higher physical properties than the HNBR. The HNBR compound and the HNBR blend gave better (lower) brittle points and better (lower) compression set values than the polyester urethane compound. Oven aging, tested at 70 hours/150 [degrees] C, showed the HNBR to have similar hardness change and elongation change as the AU-2 compound, but less loss of tensile strength. Fuel B aging, 70 hours at room temperature, showed the AU-2 compound and the 50/50 blend to have much better retention of properties than the HNBR compound, with the trends appearing linear in nature (figure 10). ASTM oil #3 exposure, for 70 hrs./150 [degrees] C, showed poorer retention of hardness and tensile with the AU-2 compound and the 50/50 blend, but lower volume swell
Roughly speaking, the sound of a guitar note is characterised by an initial 'attack' where the pick or nail produces higher pitched . This suggests that blends of HNBR with AU-2, in minor amounts, may be practical to improve specific properties Specific properties of a substance are derived from other intrinsic and extrinsic properties (or intensive and extensive properties) of that substance. For example, the density of steel (a specific and intrinsic property) can be derived from measurements of the mass of a steel bar , such as resistance to oils and fuels, without having serious deleterious deleterious adj. harmful. effects on other properties. [GRAPH OMITTED] Conclusions Solid urethane rubber is a very versatile polymer with excellent properties, especially high tensile and tear strength, and very high abrasion resistance. It also has excellent resistance to oils and similar fluids because of its polar nature. Because of this polar nature, it is very blendable with other polar rubbers such as NBR, NBR/PVC and HNBR, typically giving intermediate properties for the blends. It may also be blended with less polar polymers such as BR and SBR, and possibly even the non-polar EPDM. The benefits of adding small portions of urethane rubber to other conventional polymers are: improved abrasion resistance (depending on specific polymer and cure system); improved tensile and tear strength (depending on specific polymer and cure system); improved retention of properties at high temperature; improved oil and solvent resistance; and improved low temperature properties (NBR/PVC). The benefits of adding rubber to urethane are: improved reversion resistance; improved compression set (NBR); improved resistance to water, glycol glycol (glī`kōl), dihydric alcohol in which the two hydroxyl groups are bonded to different carbon atoms; the general formula for a glycol is (CH2)n(OH)2. , MEK; and lower compound cost. Urethane can generally improve the properties of polymers it's it's 1. Contraction of it is. 2. Contraction of it has. See Usage Note at its. it's it is or it has it's be ~have added to, and when small portions of other polymers are added to it, a lower cost compound with many of the good properties of urethane can be the result. Optimizing the cure system and polymer blend ratio, in most cases, can result in compounds that perform in the most cost effective manner. Acknowledgements "Blends of PU with conventional rubbers" is based on a paper given at the April, 1999 meeting of the Rubber Division. "Novel TPVs exhibit excellent adhesion adhesion /ad·he·sion/ (ad-he´zhun) 1. the property of remaining in close proximity. 2. the stable joining of parts to one another, which may occur abnormally. 3. to textile textile Any filament, fibre, or yarn that can be made into fabric or cloth, and the resulting material itself. The word originally referred only to woven fabrics but now includes knitted, bonded, felted, and tufted fabrics as well. fibers during melting process" is based on a paper given at the September September: see month. , 1999 meeting of the Rubber Division. "HNBR roll covers for severe conditions" is based on a paper given at the September, 1999 meeting of the Rubber Division. |
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