=?iso-8859-1?Q?Insulation_of_HBT=B4s_-Reply?=

To: tesla-at-pupman-dot-com
Subject: =?iso-8859-1?Q?Insulation_of_HBT=B4s_-Reply?=
From: ROBERT CRESSLER <59CREROB-at-menasha-dot-com> (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Thu, 08 Oct 1998 20:56:32 -0600
Approved: terryf-at-verinet-dot-com


      coiliers! at last mu subject!
poly,PE,polyethylene.... beware on using this as a generic call out for the
entire family of the ethylene.....
the main demarcation of the various types is in the molecular wt. of the
polymer chain. as the MW goes up so do the physical properties of the
material.
LLDPE---trash bags and the like
LDPE--- plastic totes,squeeze bottles,ect.
HDPE--- milk bottles,chemical tanks,....
UHMWPE--- mechanical components,wear surfaces,ect.
chemical&electrical performance is different from type to type.
I agree with reinhard that after about 80*C most of the PE's  will at the
limited of there range. (uhmw actually melts at 135*C or
so).however,temp aside the clear choice should be uhmw for electrical
applications. hdpe in a pinch and ldpe only under duress.
breakdown voltage is double and surface resistivity is several orders of
magnitude greater for uhmw than the other PE's. for higher temperatures
polypropylene 200*F,polycarbonate275*F,ect not to mention the exotic
ones... ultem,kapton,teflon,kynar.... and rest of the "gold" of the plastics
world.

a great source for uhmwpe tape & film is: Crown Plastics co.
116 may drive 
Harrision,oh.45030 USA
800-368-0238-ph
513-367-4004-fax
 reinhard,
               as for europe,the premier uhmw producer of them all is:
Poly Hi Solidur/intl.

p.o.box 1264
 48685 vreden,germany 
telefon 02564.301291
telefax 02564.301244

...... sorry tc'er for such a long ramble.
Robert