Recipe for Low-Viscosity Epoxy Resin

Resin components

EMBed-812 (glycerol polyglycidyl ether; EMS catalog# 14900 or 14901)
NSA (noneyl succinic anhydride; EMS catalog# 19050 or 19051)
NMA (nadic methyl anhydride; EMS catalog# 19000 or 19001)
BDMA (benzyldimethylamine; EMS catalog# 11400 or 11400-25)

Workflow

Make Mixture A with EMBed-812 and NSA
Make Mixture B with EMBed-812 and NMA
Make working resin with Mixture A, Mixture B, and BDMA

How to determine the amounts of resin components in each mixture

Use this formula (Luft, 1961):

W_A: weight (g) of anhydride (NSA or MNA) required
M_A: molecular weight (g/mol) of anhydride (NSA = 224.269; NMA = 178.185)
W_E: weight (g) of epoxy monomer (EMBed-812)
W_PE: weight per epoxide equivalent (This “WPE number” is indicated on EMBed-812 bottle and varies batch-to-batch.)

For Mixture A, assuming W_E = 10 g of EMBed-812 with WPE of 144, the amount of NSA would be: 0.7 × 224.269 × 10 / 144 = 10.9 g

For Mixture B, assuming W_E = 10 g of EMBed-812 with WPE of 144, the amount of NMA would be: 0.7 × 178.185 × 10 / 144 = 8.66 g

For the final working resin, mix 3 parts A with 7 parts B. When fully mixed, add BDMA (2% of A+B by weight). Example: 3 g of A + 7 g of B + 0.2 g of BDMA

The cutting quality of the resin block can be adjusted by changing the ratio of Mixtures A and B (see Luft, 1961).

Reference

Luft JH. (1961) Improvements in epoxy resin embedding methods. J Cell Biol 9:409-414. IMPROVEMENTS IN EPOXY RESIN EMBEDDING METHODS