Sintra board

Sintra has been failing our Oddy tests.  Our last "Sintra" sample
(manufactured by 3A Composites) that passed Oddy testing was in Feb
2011.  Since January of this year, we have tested recent batches of
Sintra and Celtec brands of expanded PVC board 3 times and all
samples have failed.  Our distributor, Laird Plastics, is the same
since the passing 2011 sample.  Our Oddy procedure has not changed,
and the conservator performing the tests is the same.  Our sample
sizes are approximately 1cm cubes.

Has anyone else had instances of Sintra failing?  Has anyone heard
of a formulation change?  Or variation in the results depending on
sample size or the thickness of the sample boards?  Would anyone be
willing to do a sample swap to see if our Oddy tests match up?

Jennifer Kim
Associate Conservator
Autry National Center of the American West
4700 Western Heritage Way
Los Angeles CA 90027-1462
323-495-4355


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                  Conservation DistList Instance 28:8
                   Distributed: Friday, July 25, 2014
                        Message Id: cdl-28-8-009
                                  ***