The curing agent was based on MTHPA with an anhydride equivalent weight ([W.sup.A.sub.eq]) of 169 g/eq.
where [W.sup.RD] and [W.sup.A] are the added masses of DGEBD and MTHPA, respectively.
The total heat of reaction, [DELTA]H, is taken as 49.3, 54.4, and 58.6 kJ/eq for systems containing 3, 4, and 5.5 %wt BTEAC in MTHPA, respectively .
BTEAC in MTHPA at [T.sub.a] = 35[degrees]C and To = 40[degrees]C.
Blending was performed in a one-stage process by the direct mixing of epoxy precursors with a stoichiometric amount of MTHPA
and a 1MI (3 wt% on the basis of the anhydride weight).
After incorporation with 12.2 g of MTHPA
and 0.15 g of DMP30, the mixture was magnetically stirred for another 15 min, and cured at 100[degrees]C for I h and at 150[degrees]C for another 2 h in a plastic mold.
, and 1-MI were mixed together at their equivalent ratios to prepare the epoxy matrix system.
The mixture was stirred with a magnetic stirrer for 15 min at room temperature, and then stoichiometric amounts of MTHPA
and 0.2-mL promoters were added.
The mixture was stirred with a magnetic stirrer for 15 min at room temperature and then stoichiometric amount of MTHPA
and 0.2 ml promoters were added.
Since the use of MTHPA
with Cloisite 30B organo-clay nanoplatelets resulted in better exfoliation and larger expansion of intercalated clay nanoplatelets when compared with the use of TETA, it could be concluded that the organic modification with MT2EtOH is more suitable with MTHPA
than with TETA.
Figure 2 shows the storage modulus at 30 [degrees]C, which is measured by DMA, of the DGEBF and the biobased neat epoxies cured with the anhydride curing agent, MTHPA
. In Fig.
In order to assess the possibility of the reaction's taking place between styrene, N-phenylmaleimide and the double bond in the hardener (MTHPA
) during the simultaneous polymerization process, two copolymers were prepared (with and without hardener) in THF at 70 [degrees] C.