Eastman 1,4-CHDA versus IPA, AD, and HHPA
in a Highsolids Resin System Based on TMPD Glucol, Eastman Publication N-335A, April 1996
"We used the same colors in the Stokes wing and Main Building but jazzed up the hue," says Dana Pizzetta, interior designer and library planner, HHPA. A palette of several accent colors highlights the rich tones throughout the new wing.
According to HHPA, "A welcoming and energetic spirit embraces visitors as soon as they enter into the main lobby." Two brushed aluminum circulation desks are located along a large curved wall within two arches detailed in multi-colored tile patterns.
The HHPA resins were tested in compression to eliminate brittle failure of the polymer and observe the effect of the additive on the yield strength of the material.
Using a curing agent that does not generate hydrogen bonding-donating moieties (HHPA), it was found that the formation of strong hydrogen bonds between the additive and the polymer is not a requirement for antiplasticization.
A comparison of the hydrolytic velocity of the HHPA.NPG oligoester [1.3 [mg.sub.KOH]/([g.sub.resin] *day)] to the 1,3-CHDA.NPG oligoester revealed that the HHPA-based oligoester was 2500% lower, and the HHPA.NPG oligoester was 1800% lower when compared to the 1,4-CHDA.NPG oligoester.
When comparing the HHPA.CHDM oligoester [3.0 [mg.sub.KOH]/([g.sub.resin] *day)] to the 1,3-CHDA.
DDSA (dodecenyl succinic anhydride) is offered for producing tougher, more flexible cured polymers; Succinic anhydride (SAA) is recommended for applications where a dibasic acid anhydride is desired; and HHPA
(hexahydrophthalic anhydride) hardener is also recommended for curing epoxies.
IPN formulations were produced by first mixing a bisphenol-A epoxy resin (Epikote 828, supplied by Shell Chemical) with 80 phr hexahydrophthalic anhydride (HHPA
), (supplied by Ciba-Geigy under the trade name of Hardner HT907) until a clear solution was obtained.
The firm of Hardy Holzmann Pfeiffer Associates (HHPA
) has undertaken the intricate project of transforming the turn-of-the-20th-century Victory Theater into the fully-equipped 21st-century New Victory, providing state-of-the-art performance facilities while conserving and restoring the theater's intimate proportions and historic details.