108
4.
EMBEDDING
4.10. Araldite Embedding
Maal0e and Birch-Andersen (1956) first achieved partial success with
an epoxy resin embedding medium. The particular resin they chose was
not very satisfactory, and subsequently Glauert et al. (1956) developed
Araldite as a more effective embedding substance. Later, Glauert
and Glauert (1958) and Glauert (1961) detailed improved ways of handling this embedment. It should be realized from the outset, however,
that the English Araldite which they used is not quite the same product
as the Araldite which has been commonly available in the United States.
Thus, in general, Americans have had to develop somewhat different procedures to utilize easily available resins.
The Glauerts' embedding mixture consists of equal parts of Araldite
M and the hardener 964B (dodecenyl succinic anhydride), to which is
added 5% of an accelerator, 964C (2,4,6-tridimethylaminomethylphenol),
commonly known in the United States as DMP-30. Hardness is controlled
by adding the plasticizer, dibutyl phthalate, in quantities up to 10%. This
plastic mixture polymerizes in 2 days at 48°C, although it is perhaps best
to expose the capsules to 60°C for at least the last day.
The plastic components used by the Glauerts are available from Aero
Research Ltd., Duxford, Cambridge, and from Fluka AG Chemische Fabrik, Buchs SG, Switzerland. Cartel agreements, however, seemingly have
prevented the American Ciba Co. from importing the Araldite M resin
into this country even though it is made by the Swiss counterpart company. However, the International Chemical and Nuclear Corp., City of
Industry, California, has announced that it is making this resin available
as part of a complete embedding kit, sold as Durcupan ACM.
The epoxy resin manufactured in the United States which seems to be
most nearly similar to Araldite M, is known as 502. The latter is not a
pure resin, but is said to contain a small quantity of dibutyl phthalate.
Likewise, Araldite M is a resin blended with a "modifier" that apparently
is a company secret.
Luft (1961) introduced two significant changes in the original embedding procedure, which made it possible to use very effectively Araldite
502 (Ciba Co., Inc., Plastics Division, Kimberton, Pennsylvania). The most
fundamental of these changes was to alter the ratio of the anhydride
hardener to the epoxy resin to 0.7. Thus, his formulation is Araldite
502, 27 ml, DDSA (dodecenyl succinic anhydride), 23 ml, plus 1.5-2.0%
4.
EMBEDDING
4.10. Araldite Embedding
Maal0e and Birch-Andersen (1956) first achieved partial success with
an epoxy resin embedding medium. The particular resin they chose was
not very satisfactory, and subsequently Glauert et al. (1956) developed
Araldite as a more effective embedding substance. Later, Glauert
and Glauert (1958) and Glauert (1961) detailed improved ways of handling this embedment. It should be realized from the outset, however,
that the English Araldite which they used is not quite the same product
as the Araldite which has been commonly available in the United States.
Thus, in general, Americans have had to develop somewhat different procedures to utilize easily available resins.
The Glauerts' embedding mixture consists of equal parts of Araldite
M and the hardener 964B (dodecenyl succinic anhydride), to which is
added 5% of an accelerator, 964C (2,4,6-tridimethylaminomethylphenol),
commonly known in the United States as DMP-30. Hardness is controlled
by adding the plasticizer, dibutyl phthalate, in quantities up to 10%. This
plastic mixture polymerizes in 2 days at 48°C, although it is perhaps best
to expose the capsules to 60°C for at least the last day.
The plastic components used by the Glauerts are available from Aero
Research Ltd., Duxford, Cambridge, and from Fluka AG Chemische Fabrik, Buchs SG, Switzerland. Cartel agreements, however, seemingly have
prevented the American Ciba Co. from importing the Araldite M resin
into this country even though it is made by the Swiss counterpart company. However, the International Chemical and Nuclear Corp., City of
Industry, California, has announced that it is making this resin available
as part of a complete embedding kit, sold as Durcupan ACM.
The epoxy resin manufactured in the United States which seems to be
most nearly similar to Araldite M, is known as 502. The latter is not a
pure resin, but is said to contain a small quantity of dibutyl phthalate.
Likewise, Araldite M is a resin blended with a "modifier" that apparently
is a company secret.
Luft (1961) introduced two significant changes in the original embedding procedure, which made it possible to use very effectively Araldite
502 (Ciba Co., Inc., Plastics Division, Kimberton, Pennsylvania). The most
fundamental of these changes was to alter the ratio of the anhydride
hardener to the epoxy resin to 0.7. Thus, his formulation is Araldite
502, 27 ml, DDSA (dodecenyl succinic anhydride), 23 ml, plus 1.5-2.0%