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Polymer Question - PVC (1 Viewer)

bayan92

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Did you answer it by saying:

1. Crude oil cracked to get ethene
2. Ethene undergoes substitution with chlorine gas
3. Chloroethene undergoes addition polymerization to form PVC
4. PVC heated and molded to pipe shape
 

mR sinister

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i chose polyethylene Bottle.
yea i talked about crude oil into ethene
Ethene to Ethane.
Ethene addition polymerisation with:
-iniation
-propagation
-termination

Then how HDPE is formed, and HDPE properties
Then finally HDPE used to make bottle :D

darn, should of chose PVC since its thermoplastic, would of been easier... ohh well
 

Imagination

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didint for the polyethylene bottle, have to talk about LDPE and not HDPE??
 

sharp_pencil

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i chose polyethylene Bottle.
yea i talked about crude oil into ethene
Ethene to Ethane.
Ethene addition polymerisation with:
-iniation
-propagation
-termination

Then how HDPE is formed, and HDPE properties
Then finally HDPE used to make bottle :D

darn, should of chose PVC since its thermoplastic, would of been easier... ohh well
Dude plastic bottles are LDPE..... :| but i guess they'll accept HDPE mayybeee
 

clintmyster

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Dude plastic bottles are LDPE..... :| but i guess they'll accept HDPE mayybeee
I doubt it because HDPE is nowhere near as flexible. The question said "raw" right? Gahh I started from ethene =[ there goes a couple of marks.
 

TechnIx

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I used Cellulose as raw material........................oh man
Me too! It's ok, it said Natural Resource (which includes either Cellulose or Crude Oil)

I freaked out for a second there too.

didint for the polyethylene bottle, have to talk about LDPE and not HDPE??
Yeah I did LDPE, which I believe is correct. It's low density, branched, structure makes it soft, yet tough and flexible. Perfect for a plastic bottle. Then other additives etc for colouring, shaping, whatever...

LDPE formed with oxygen free radical, high pressure and 80-300 degrees.
 

sordatsoy

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I didnt mention LDPE OR HDPE.. after i talked about cracking crude oil, i just talked about initiation, propagation and termination....then i talked about how it is made into a bottle....would i lose marks for not mentioning which type (LDPE/HDPE) it is?
 

Monsterman

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^
you may a mark? i think
i didnt mention raw materials
started from ethene.. =\
 

nosh22

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Yeah I did the polyethylene bottle. Assumed it was HDPE.
 

5233andy

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I went on about the fermentation of glucose, the production of ethanol, the dehydration of ethanol, the polymerisation of ethene... I didn't talk about HDPE/LDPE... oh gosh...
 

arjungamer123

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Me too! It's ok, it said Natural Resource (which includes either Cellulose or Crude Oil)

I freaked out for a second there too.



Yeah I did LDPE, which I believe is correct. It's low density, branched, structure makes it soft, yet tough and flexible. Perfect for a plastic bottle. Then other additives etc for colouring, shaping, whatever...

LDPE formed with oxygen free radical, high pressure and 80-300 degrees.
Guys (and girls), I don't think some of you are thinking. LDE makes plastic bags for shopping. Imagine carrying water in that!

HDPE is the safe option here. They can't fault you for saying HDPE, because HDPE is used in milk bottles- aka a type of bottle.

EDIT: OP, question said NATURAL RAW PRODUCT- not sure if they'll accept crude oil. I think they wanted you to go through the cellulose process of doing ish.
 
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TechnIx

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I went on about the fermentation of glucose, the production of ethanol, the dehydration of ethanol, the polymerisation of ethene... I didn't talk about HDPE/LDPE... oh gosh...
Dont stress, you've covered most of it. 1 mark at most you've lost.

Hell, those who did mention it seemed to not know which one it is anyway.....

Guys (and girls), I don't think some of you are thinking. LDE makes plastic bags for shopping. Imagine carrying water in that!

HDPE is the safe option here. They can't fault you for saying HDPE, because HDPE is used in milk bottles- aka a type of bottle.

EDIT: OP, question said NATURAL RAW PRODUCT- not sure if they'll accept crude oil. I think they wanted you to go through the cellulose process of doing ish.
Good reasoning, however I'm reading here in my Excel book for LDPE ;
"It is readily melted and moulded and is used to produce such items as flexible film wrap, sandwich bags, plastic bags, and PLASTIC SQUEEZE BOTTLES"

As for HDPE, it says petrol containers, rubbish bins plastic crates.
HDPE just seems too tough to be honest.

I think either will be OK, as I do know that milk bottles are made from HDPE (or is that just their tough lid where it says HDPE? I cant remember). It may just be the milk bottle lid that is HDPE lol.
 

untouchablecuz

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what i put:

biomass raw material
cellulose derived from biomass (wrote formula)
cellulose (broken down by various enzymes) --> maltose --> glucose
glucose fermented and ethanol obtained (wrote equation)
ethanol dehydrated to ethene+water in the presence of conc. H2SO4
ethene LDPE process (+ equation)
"since LDPE is thermoplastic, it can be melted down and moulded to create bottles"
 

kandyman

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Catalytic cracking of larger petrochemicals (ex decane) forming ethene. Substitution reaction to produce the chloroethene, then the chloroethene is subjected to pressures up to 300 mPa, and an initiator molecule is added (dodecyl peroxide). The initiator molecule breaks down to form free radicals, which join onto the chloroethene to produce activated free monomers, which then propagate to form the chain. The initiator molecule is then reintroduced to terminate the chain. Once the polycholoroethene is produced, it is shaped and moulded to form the PVC pipe.
 

Fortify

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I used Cellulose as raw material........................oh man
dw, i did that as well :)

I doubt it because HDPE is nowhere near as flexible. The question said "raw" right? Gahh I started from ethene =[ there goes a couple of marks.
uh oh i used HDPE cos i always thought LDPE was plastic bags, cling wrap :/
 

imoO

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Shit...

I said that
physically - the momomers link together forming a long chain blah blah

chemically -
initiation
propagation
termination....

i didn't talk about how its produced from ethanol or shit like that...

what d'you rekon ?
 

Fortify

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Shit...

I said that
physically - the momomers link together forming a long chain blah blah

chemically -
initiation
propagation
termination....

i didn't talk about how its produced from ethanol or shit like that...

what d'you rekon ?
LOL . from 'raw materials' :/
 

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