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Polymeric materials

Polymeric materials

Polymeric materials

(OP)
Is there any Polymer ( preferably available commercially ) which has the following properties...it should be amorphous,have Tg around 50-60 deg C with the catch that it should have a phenylene group(s) in its main chain. Thanks in advance.

RE: Polymeric materials

Modified PPO (mPPO) - a blend of polystyrene (PS) and polyphenylene oxide has a Tg depending on the ratio of PS to PPO.

Trade names are such as Noryl (Sabic, used to be GE). There are others.

mPPO and PS might be able to be dry bulk mixed prior to processing to get the Tg you require.

Cheers

H

www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.

RE: Polymeric materials

An amorphous polymer is so common most are 100% amorphous- crystallinity is the difficult property to achieve- the main polymer chain needs to be symmetrical and linear with limited side chains and careful processing.

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RE: Polymeric materials

(OP)
Thanks for your reply
Well,let me clarify further .I will studying the phenyl flips in the main chain of the polymer using NMR analysis.Using a polymer blend might complicate the test,so it will have to be a Homopolymer. Anyway I am looking at polyethylene isophthatate as an option.It seems Okay as far as the Tg is concerned but i cant find its structure anywhere on the internet.Sigma-Aldrich has it on its product list. Any help??? Also will be grateful for any other suggestion pertaining to my requirements.

RE: Polymeric materials

As you probably know, Tg depends on testing speed. So the Tg will not be anywhere near 50-60C under NMR conditions.

Your study may be hard. A homopolymer with a phenyl group will have a Tg way higher than 50-60C because those groups are so rigid.

Blends, as you said, are problematic.

A copolymer is an option but block copolymers with a Tg of 50-60C will not have any flips in the phenyl portion of the copolymer because it's too stiff and its Tg is way higher than that.

Random copolymers fulfill your stated criteria but would have a very messy NMR spectrum messing up your analysis.

By a process of elimination your best option is an alternating copolymer as that could have the Tg you want and a regular structure to simplify analysis.

Chris DeArmitt

Expert consulting & training
www.phantomplastics.com

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