The effect of CTBN concentrations on the kinetic parameters of decomposition of blends of cardanol‐based epoxidized novolac resin modified with carboxyl‐terminated liquid copolymer

Abstract

Cardanol-based novolac resins were separately prepared with different mole ratios of cardanol-toformaldehyde with different acid catalysts. These resins were epoxidized with epichlorohydrin, in basic medium, at 120 C. The resins were, separately, blended with different weight percentages of carboxyl-terminated butadiene acrylonotrile copolymer and cured with polyamine. Structural changes during blending were studied by FTIR spectroscopic analysis. Coats-Redfern equation was utilized to calculate the kinetic parameters, viz., order of decomposition reaction (n), activation energy (E), pre-exponential factor (Z), and rate decomposition constant (k), for the decomposition of the samples. It was found that the degradation of the epoxies and their blend samples proceeded in two steps.

Thermal-Degradation Kinetics of Neem-Alginate-Clay Based Controlled Pesticide Release Formulations

“…The data on initial decomposition temperature (T 0 ), final decomposition temperature (T f ), final residues left at T f and temperatures of maximum rate of weight loss (T max ) are shown in Table 3. Initial decomposition temperature (T 0 ) is corresponding to the first detectable temperature at which the degradation of the material starts and has been considered after the initial loss of physically absorbed water and structural water (dehydration reactions) [25]. From non-isothermal TG/DTG data, the degradation mechanism and thermal kinetics were evaluated by applying seven kinetic degradation models and the results are presented in Table 4.…”

Synthesis, Spectral and Thermal Degradation Kinetics of the Epoxidized Resole Resin Derived from Cardanol

“…Absorption bands near 2855 and 2925 cm −1 appeared in the spectrum, indicating the presence of the methylene group (-CH 2 ) in the cardanol, RCF 117 , and ERCF 117 . [26][27][28] The peak at 1264 cm −1 could be due to the presence of asymmetric vibration of the C-O-C linkage, and an absorption band near 1457 cm −1 might be related to the orthosubstituted aromatic ring.…”

“…The appearance of a peak at 3.9 ppm showed the presence of benzylic and methylene protons of C 6 H 5 .CH 2 .C 6 H 5 for the bridge between the phenyl groups. [26][27][28]…”

Flexible epoxy novolac coatings: Use of cardanol‐based flexibilizers

“…Particularly, in coating application, epoxy resins exhibit excellent adhesion to heterogeneous materials with high resistance to water and chemicals . The most commonly used epoxy resins are based on glycidyl ethers of bisphenol‐A (BPA) which are obtained by the reaction between bisphenol‐A and epichlorohydrin (ECH) .…”

“…But, most types of epoxy resins/epoxy novolacs exhibit an inherent brittleness due to the typical glassy crosslinked structure of the polymer. The successful strategy of enhancing the toughness of rigid epoxy/epoxy novolac resins involves the incorporation of flexibilizers such as liquid rubbers (like CTBN, ATBN, etc hyperbranched polymers, polysulphides which react during curing and form an integral part of the 3‐D network …”