Cellulose Acetate Degradation
Cellulose Acetate Degradation
(OP)
I have some cellulose acetate that is degrading. It has become very brittle. I was thinking that it is from glycosidic cleavage of the polymer, but I do not know what is causing this. Also what causes plasticizers (Diethyl Phthalate and Dimethyl Phthalate and Triphenyl Phosphate to leech out? Is it the hydrolysis of the Acetate groups causing acetic acid that makes the plasticizer come out or does it just come out on its own after a certain amount of time. Is ther a certain material that will cause the plasticizer to come out faster than it normally would?






RE: Cellulose Acetate Degradation
The plasticiser migrates out in an attempt for it to reach equilibrium with it's surroundings. Higher molecular weight plasticisers or less active molecules leach out at a slower rate. Cellulose acetate is particularly sensitive to UV light.
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RE: Cellulose Acetate Degradation
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RE: Cellulose Acetate Degradation
And yet there is no vinegar smell on any of the samples at all. Does anyone think that all this cracking and brittleness came from just the loss of the plasticizer? Because if the Cellulose Acetate was degrading then there should at least be a vinegar smell which indicates the acetate groups being hydrolyzed.
I will be running Raman-IR on the samples soon to make sure that the information that I recieved was correct in the fact that they are cellulose acetate.
Also any opinions on certain elements that were used to achieve different pigments having an effect on the degradation? The samples are being analyzed with an XRF.
Please, any thoughts on Cellulose Acetate degradation would be helpful!
Thanks
RE: Cellulose Acetate Degradation
They can act as nucleating agents having an effect on degree of crystallinity and size and shape of crystals. Even some so called amorphous polymers have some nano sized crystals.
They can act as a catalyst to oxidation, cross linking or any other reaction. Many colorants contain metals.
They can act as a blind to protect the matrix from UV attack.
They can effect the temperature as visible light is absorbed and converted to heat, or is reflected to various degrees.
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