What is vulcanization? What effect does it have on rubber? How does vulcanization molecularly affect the rubber?
Re: Materials Science C
Posted: February 26th, 2018, 9:47 am
by Tesel
Name wrote:What is vulcanization? What effect does it have on rubber? How does vulcanization molecularly affect the rubber?
Vulcanization is a process where natural rubber is heated with sulfur. It causes the rubber to become less sticky, more durable, and more useful. It creates sulfur cross-links between the rubber chains, similar to the curing of thermoplastic polymers.
Re: Materials Science C
Posted: February 26th, 2018, 12:33 pm
by Name
Tesel wrote:
Name wrote:What is vulcanization? What effect does it have on rubber? How does vulcanization molecularly affect the rubber?
Vulcanization is a process where natural rubber is heated with sulfur. It causes the rubber to become less sticky, more durable, and more useful. It creates sulfur cross-links between the rubber chains, similar to the curing of thermoplastic polymers.
Yup your turn
Re: Materials Science C
Posted: March 3rd, 2018, 3:43 pm
by IcsTam
I'm just going to post a question, if that's alright.
1. What is a copolymer?
2. Describe and differentiate between a random, alternating, block, and graft copolymer.
Re: Materials Science C
Posted: March 3rd, 2018, 5:53 pm
by Tesel
IcsTam wrote:I'm just going to post a question, if that's alright.
1. What is a copolymer?
2. Describe and differentiate between a random, alternating, block, and graft copolymer.
Yep, my bad.
1. A copolymer contains multiple different monomer units.
2A. A random copolymer has monomers randomly ordered, e.g. ABAAABBAABABBBAAB.
2B. An alternating copolymer has regularly alternating monomer units, e.g. ABABABAB.
2C. A block copolymer consists of multiple "blocks" which each contain only one type of monomer, e.g. AAAABBBBAAAAABBB.
2D. A graft copolymer has one type of monomer on the main chain and a different type of monomer on the side chains. In other words, one chain is "grafted" onto the other.
Assuming I'm right, I'll just post the next question, to make sure I don't forget.
IcsTam wrote:I'm just going to post a question, if that's alright.
1. What is a copolymer?
2. Describe and differentiate between a random, alternating, block, and graft copolymer.
Yep, my bad.
1. A copolymer contains multiple different monomer units.
2A. A random copolymer has monomers randomly ordered, e.g. ABAAABBAABABBBAAB.
2B. An alternating copolymer has regularly alternating monomer units, e.g. ABABABAB.
2C. A block copolymer consists of multiple "blocks" which each contain only one type of monomer, e.g. AAAABBBBAAAAABBB.
2D. A graft copolymer has one type of monomer on the main chain and a different type of monomer on the side chains. In other words, one chain is "grafted" onto the other.
Assuming I'm right, I'll just post the next question, to make sure I don't forget.
Amorphous plastics do not have a sharp melting point; rather, regions of the polymer soften as the temperature increases. Crystalline thermoplastic polymers have a sharp melting point and change to a liquid once that point is met fairly quickly. Thermoset polymers do not melt.
Re: Materials Science C
Posted: March 3rd, 2018, 8:50 pm
by Tesel
Yep, well done. I'd reference the glass transition point for amorphous materials on a test.
Re: Materials Science C
Posted: March 3rd, 2018, 8:57 pm
by IcsTam
Describe the function of each of the following: Plasticizer, Filler, Stabilizer, Lubricant.
Re: Materials Science C
Posted: April 8th, 2018, 1:02 pm
by JavaScriptCoder
Well, this forum seems a little dead, so I'll revitalize it.
IcsTam wrote:Describe the function of each of the following: Plasticizer, Filler, Stabilizer, Lubricant.
A plasticizer makes a material less brittle, a filler (name is a bit self-explanatory) fills gaps, a stabilizer prevents the breakdown of an emulsion (from what I've learned liquid-liquid colloids are insanely unstable) and a lubricant decreases friction.
Is it right?
Re: Materials Science C
Posted: April 8th, 2018, 5:46 pm
by IcsTam
JavaScriptCoder wrote:Well, this forum seems a little dead, so I'll revitalize it.
IcsTam wrote:Describe the function of each of the following: Plasticizer, Filler, Stabilizer, Lubricant.
A plasticizer makes a material less brittle, a filler (name is a bit self-explanatory) fills gaps, a stabilizer prevents the breakdown of an emulsion (from what I've learned liquid-liquid colloids are insanely unstable) and a lubricant decreases friction.
Is it right?
So for filler, I would specify that it improves tensile strength and directional stability in the polymer. Otherwise, that's right! Your turn