PE, that's not the enzyme. It's something else but I'm not going down that road anyway.
Here's a link to the paper I found http://dl.dropbox.com/u/4212013/Surf..._stability.pdf
It's entitled Surface structure and properties of poly-(ethylene terephthalate) hydrolyzed by alkali and cutinase, written by Ilaria Donelli, Giuliano Freddi, Vincent A. Nierstrasz, Paola Taddei, and published in a journal called Polymer Degradation and Stability. Hopefully anyone interested can open the link. Let me know if it doesn't work.
Besides plenty of things I don't quite understand, there are two things of interest in this paper regarding the treatment of PET.
1) A treatment protocol is given,
So here they tell us the concentration of NaOH, temperature and process. I am making the assumption that since these fellows are associated with the fabric and dye industry, they are citing a standard method of processing.For the alkaline treatment, PET films were immersed in a 1M NaOH aqueous solution at 40 C, for different times, from 30 min to 24 h, under agitation on a shaking bath (Isco SBH/D, 110 rpm/min). Afterwards, membranes were extensively washed with distilled water and dried at room temperature overnight.
2) The maximum necessary treatment time using the author's protocol is two hours,
WCA stands for water contact angle and refers to the amount of water beading displayed by the PET. The higher the WCA, the more beading. We want a low WCA.Interestingly, both NaOH and cutinase (the ezyme being compared Ed) lead to a levelling of the WCA values which do not change too much for treatment times longer than 2 h.
I am treating a new piece of Dura-lar now according to the information from this paper and I'll report back when I get some new results.