Tim Tyler wrote:
Mike Lyle wrote or quoted:

Perfect logic, but the fact remains that there isn't a glue for
poly[ethyl]ene, which isn't a million miles different from ptfe,
the
non-stick frying-pan stuff. It's always joined by welding. [...]

``Polyethylene and polypropylene and nylon are pretty difficult,
because they do not have any pores, and almost no solvents can
dissolve them. Only soft, rubbery solvent-drying glues can work,
because glues can only hang onto the plastic by wetting its
surface.''

- http://www.newton.dep.anl.gov/askasc.../chem03271.htm

``8005 - Scotch-Weld? Structural Plastic Adhesive
Two-part structural acrylic-based adhesive (10:1 mix ratio by
volume), that can structurally bond many grades of polyethylene,
polypropylene, and thermoplastic elastomers (TPE's) without any
surface preparation at room temperature.''

- http://www.tapecase.com/tc/prodASP/S...Structural.asp

Good news! (Note that I did mention things which work by wetting will
stick to pe in the part you cut for space.) I wonder what the
smallest available quantity is.

Of course, using it to mend a torn sheet would need you to cut strips
from another sheet, apply the adhesive, and apply them. Ready-made
mending tape still sounds quite attractive!

--
Mike.