VMI-cursus (Eng)

• Mentorles
• WO
• Studiejaar 1

What have thermoplast
and rubber in common?

1. Both are vulcanized
2. Easy to recycle
3. Very elastic
4. Consist of macromolecules

A co-polymer is made of:

1. Polymerization with copper linkages
2. Branched chains
3. Two different monomers
4. The same monomer

What happens during rubber vulcanization?

1. The chains start branching
2. An elastic network is formed
3. The rubber becomes plastic
4. After vulcanization the rubber becomes soluble

What is the influence of unsaturated C-C bonds in rubber?

1. To have a melting point
2. To vulcanize with Sulphur
3. It's a thermoplast
4. It is sensitive for ozone and UV irradiation

What is the difference in crosslinks between rubber and TPE?

1. Rubber has chemical crosslinks
2. TPE has chemical crosslinks
3. TPE has physical crosslinks
4. TPE consists of soft and hard segments

What are the most important functions of rubber? (1)

1. Connecting
2. Sealing
3. Damping
4. Separating

What are the most important functions of rubber? (2)

1. Isolation
2. Reinforcement
3. Transportation
4. Fire retardation

What is the largest contributor to filler reinforcement in rubber?

1. The color (black or light colored)
2. Particle size
3. Chemical composition
4. Density

What is the most used filler in the rubber industry? - use small caps -

Which tires mostly consist of natural rubber?

1. Passenger vehicles
2. Lorry tire
3. Bicycle tire
4. Off-road tires

From which country originates the rubber tree?

1. Brazil
2. Malesia
3. Indonesia
4. Vietnam

Advantages of butadiene rubber are:

1. High strength
2. Good abrasion resistance
3. Low glass transition temperature
4. Low heat build up during use

Which rubber is most gas tight?

1. Butadiene rubber (BR)
2. Butyl rubber (IIR)
3. Natural rubber (NR)
4. Styrene-butadiene rubber (SBR)

How to influence die-swell? (1)

1. Adjust compound formulation
2. Extruder temperature
3. Length of vulcanization unit
4. Temperature of cooling water

Which type of extruder has the highest L/D ratio?

1. Hot feed extruder
2. Cold feed extruder

How to influence die-swell? (2)

1. Extrusion speed
2. Speed of belt at the exit of the extruder

What is vulcanization?

1. Heating of rubber
2. A chemical reaction in which a network is formed
3. Shaping of a rubber
4. Mixing of ingredients in a compound

Which tests can be performed on
un-vulcanized rubber compound? (1)

1. Viscosity
2. Compression set
3. Heat build-up
4. Green-strength

Which tests can be performed on
un-vulcanized rubber compound? (2)

1. Tack
2. DMTA

What is viscosity?

1. Return to original shape
2. Science of deformation and flow
3. Resistance to flow under tension

The viscosity of rubber can be measured using:

1. Tensile tester
2. Hardness tester
3. A Mooney test apparatus
4. A tack tester

What can be measured with a Garvey-die?

1. Vulcanization properties
2. The resistance against deformation
3. Extrusion properties
4. Sealing performance

What can be measured with a tensile tester? (1)

1. Abrasion resistance
2. Modulus
3. Hardness
4. Tear resistance

What can be measured with a tensile tester? (2)

1. Rebound elasticity
2. Maximum tensile stress
3. Rolling resistance
4. Stain at failure