Characteristics of rubber (raw rubber) materials and technical requirements of some rubber products
1. Name of material: natural rubber (unreinforced vulcanized rubber)
Brand: NR
● Features and scope of application:
It has excellent elasticity, tensile strength, elongation, wear resistance, tear resistance and compression set, good electrical insulation, good processability, easy adhesion of other materials, and superior to most synthetic rubbers in comprehensive performance, but poor oil resistance, weather resistance and ozone resistance, and low resistance to acid and alkali corrosion; The heat resistance is not high, and it is not suitable for working above 100℃.
● Scope of application:
Used for tires, adhesive tapes, rubber sheets, hoses, shock absorbing parts, sealing parts, hovercraft booms, wire and cable insulation layers and other general rubber products.
● Chemical composition: rubber hydrocarbon (polyisoprene) is the main component, and a small amount of protein, water, resin acid, sugar and inorganic salts are also contained.
● Performance:
Breaking strength (MPa): 16.7 ~ 28.4
Elongation at break (%): 650 ~ 900
Rebound rate (%): 70 ~ 95
Compression ratio (%): 100 ℃× 70h:+10 ~+50
Hardness (Shore A): 20 ~ 100
Long-term working temperature (℃):-55 ~+70.
Maximum service temperature (℃): 100℃
Brittle temperature (℃):-50 ~-70.
Expansion rate (%): gasoline:+80 ~+300.
Benzene:+200 ~+500
Acetone: 0 ~+10
Ethanol:-5 ~+5
Oil resistance (mineral oil): poor
Oil resistance (animal and vegetable oils): poor
Alkali resistance: fair to good
Acid resistance: strong acid: poor;
Weak acid: fair to good
Flame resistance: poor
Air tightness: good
2. Name of material: natural rubber (reinforced vulcanized rubber)
Brand: NR
● Features and scope of application:
It has excellent elasticity, tensile strength, elongation, wear resistance, tear resistance and compression set, good electrical insulation and processability, and is easy to be bonded with other materials. It is superior to most synthetic rubbers in comprehensive performance, but it has poor oil resistance, weather resistance and ozone resistance, and low corrosion resistance to acid and alkali. The heat resistance is not high, and it is not suitable for working above 100℃.
● Scope of application:
Used for tires, adhesive tapes, rubber sheets, hoses, shock absorbing parts, sealing parts, hovercraft booms, wire and cable insulation layers and other general rubber products.
● Chemical composition: mainly rubber hydrocarbon (polyisoprene), with a small amount of protein, moisture, resin acid, sugar and inorganic salt.
● Performance:
Breaking strength (MPa): 24.5 ~ 34.3
Elongation at break (%): 650 ~ 900
Rebound rate (%): 70 ~ 95
Compression ratio (%): 100 ℃× 70h:+10 ~+50.
Hardness (Shore A): 20 ~ 100
Long-term working temperature (℃):-55 ~+70.
Maximum service temperature (℃): 100℃
Brittle temperature (℃):-50 ~-70.
Expansion rate (%): gasoline:+80 ~+300.
Benzene:+200 ~+500
Acetone: 0 ~+10
Ethanol:-5 ~+5
Oil resistance (mineral oil): poor
Oil resistance (animal and vegetable oils): times
Alkali resistance: fair to good
Acid resistance: strong acid: times; Weak acid: fair to good
Flame resistance: poor
Air tightness: good
3. Material name: styrene-butadiene rubber
Brand: SBR1500 (qualified product)
● Features and scope of application:
It has the characteristics of wear resistance, heat resistance, light resistance, oxidation resistance and aging resistance, and is superior to natural rubber, but its elasticity and tear resistance are not as good as natural rubber. Soluble in toluene, gasoline and chloroform.
● Scope of application:
Used for tires, damping parts and sealing parts, as well as rubber plates, rubber hoses, rubber shoes, etc.
● Chemical composition: Butadiene and styrene monomers are used as main raw materials, and potassium rosin soap or its mixed soap is used as emulsifier, which is prepared by low-temperature emulsion polymerization.
It has the characteristics of wear resistance, heat resistance, light resistance, oxidation resistance and aging resistance, and is superior to natural rubber, but its elasticity and tear resistance are not as good as natural rubber. Soluble in toluene, gasoline and chloroform.
● Scope of application:
Used for tires, damping parts and sealing parts, as well as rubber plates, rubber hoses, rubber shoes, etc.
● Chemical composition: Butadiene and styrene monomers are used as main raw materials, and potassium rosin soap or its mixed soap is used as emulsifier, which is prepared by low-temperature emulsion polymerization.
It has the characteristics of wear resistance, heat resistance, light resistance, oxidation resistance and aging resistance, and is superior to natural rubber, but its elasticity and tear resistance are not as good as natural rubber. Soluble in toluene, gasoline and chloroform.
● Scope of application:
Used for tires, damping parts and sealing parts, as well as rubber plates, rubber hoses, rubber shoes, etc.
● Chemical composition: Butadiene and styrene monomers are used as main raw materials, and potassium rosin soap or its mixed soap is used as emulsifier, which is prepared by low-temperature emulsion polymerization.
● Chemical composition: It is prepared by emulsion polymerization with butadiene and styrene as raw materials, pullulan as emulsifier, potassium persulfate as initiator and regulator butyl as regulator.
● Performance:
Tensile strength (MPa) ：≥23
Elongation at break (%): ≥ 500
Rebound rate (%): ≥ 36
7. Name of material: cold-resistant styrene-butadiene rubber
Brand: SBR10
●Scope of application:
Mainly used for all kinds of cold-resistant rubber products.
● Chemical composition: It is prepared by emulsion polymerization with butadiene and styrene as raw materials, pullulan as emulsifier, potassium persulfate as initiator and regulator butyl as regulator.
● Performance:
Tensile strength (MPa) ：≥19
Elongation at break (%): ≥ 500
Rebound rate (%): ≥ 35
8. Name of material: insulating styrene-butadiene rubber
Brand: DBJ-3001
● Scope of application:
Mainly used for all kinds of electrical rubber products such as wires, cables and insulating rubber sheets.
● Chemical composition: It is made from butadiene and styrene by emulsion polymerization at low temperature in the presence of various additives.
9. Name of material: polybutadiene rubber (unreinforced vulcanized rubber)
Brand: BR
● Features and scope of application:
The structure is basically the same as that of natural rubber. It has high elasticity, excellent wear resistance, good aging resistance, excellent low temperature resistance, low calorific value under dynamic load, easy to bond with metal, but low strength, poor tear resistance, poor processability and self-adhesion.
● Scope of application:
Generally, it is mixed with natural or styrene-butadiene rubber, which is mainly used for tires, conveyor belts, adhesive tapes, sponge rubber and special cold-resistant products.
● Chemical composition: cis-structure rubber polymerized from butadiene.
● Performance:
Breaking strength (MPa): 0.98 ~ 9.8
Elongation at break (%): 200 ~ 900
Rebound rate (%): 70 ~ 95
Compression ratio (%): 100 ℃× 70h:+2 ~+10.
Hardness (Shore A): 10 ~ 100
Long-term working temperature (℃):-70 ~+100℃
Maximum service temperature (℃): 120℃
Brittle temperature (℃):-73.
Expansion rate (%): gasoline:+75 ~+250.
Benzene:+150 ~+500
Acetone:+10 ~+30
Ethanol:-5 ~+10
Oil resistance (mineral oil): poor
Oil resistance (animal and vegetable oils): poor
Alkali resistance: fair to good
Acid resistance: strong acid: poor ; Weak acid: second to worse
Flame resistance: poor
Air tightness: poor
10. Name of material: polybutadiene rubber (reinforced vulcanized rubber)
Brand: BR
● Features and scope of application:
The structure is basically the same as that of natural rubber. It has high elasticity, excellent wear resistance, good aging resistance, excellent low temperature resistance, low calorific value under dynamic load, easy to bond with metal, but low strength, poor tear resistance, poor processability and self-adhesion.
● Scope of application:
Generally, it is mixed with natural or styrene-butadiene rubber, which is mainly used for tires, conveyor belts, adhesive tapes, sponge rubber and special cold-resistant products.
● Chemical composition: cis-structure rubber polymerized from butadiene.
● Performance:
Breaking strength (MPa): 17.6 ~ 24.5
Elongation at break (%): 450 ~ 800
Rebound rate (%): 70 ~ 95
Compression ratio (%): 100 ℃× 70h:+2 ~+10.
Hardness (Shore A): 10 ~ 100
Long-term working temperature (℃):-70 ~+100℃
Maximum service temperature (℃): 120℃
Brittle temperature (℃):-73.
Expansion rate (%): gasoline:+75 ~+250.
Benzene:+150 ~+500
Acetone:+10 ~+30
Ethanol:-5 ~+10
Oil resistance (mineral oil): poor
Oil resistance (animal and vegetable oils): poor
Alkali resistance: fair to good
Acid resistance: strong acid: poor; Weak acid: second to worse
