Abstract

LISPERGUER, JUSTO; DROGUETT, CYNTHIA; RUF, BEATRIZ  and  NUNEZ, MARIO. DIFFERENTIAL SCANNING CALORIMETRY AND DINAMIC MECHANICAL ANALYSIS OF PHENOL-RESORCINOL-FORMALDEHYDE RESINS. J. Chil. Chem. Soc. [online]. 2005, vol.50, n.2, pp. 451-453. ISSN 0717-9707.  doi: 10.4067/S0717-97072005000200002.

Differential scanning calorimetry ( DSC ) and dinamic mechanical analysis ( DMA ) were use to study the curing reactions of two phenol - resorcinol- formaldehyde ( PRF ) adhesives with 15 and 25 % resorcinol content, synthesized in laboratory. The PRF resin with lower resorcinol content ( PRF₁ ) shows a double exothermic peak ( 99.9 and 158.2 °C ) while PRF₂ ,with greater resorcinol content ( 25 %) shows only one peak at 93.9 °C. The DMA storage modulus E' confirm the differences in the curing behavior of PRF adhesives. In the delamination resistance test during accelerated exposure only PRF₂ with a greater content of resorcinol, fulfilled the ASTM D 2559 requirements for beams treated with two CCA retention levels. The cross-linking reactions was produced in the curing process at lower temperature in PRF₂ , enhanced the adhesion durability to glulams treated with CCA preservatives