Preparation and properties of water‐soluble‐type sizing agents for carbon fibers

Flexible epoxy novolac coatings were developed by reacting an epoxy novolac resin, poly[(phenylglycidyl ether)-co-formaldehyde] (PPGEF) with an amine curing agent, 4,4 0 -diamino-3,3 0 -dimethyldicyclohexyl methane (BMCHA), cardanol based reactive diluent (Cardolite NC-513) and two different cardanol-based flexibilizers (Cardolite NC-514 and Cardolite NC-547). The flexibilizer content was varied from 5 to 10% by weight of the resin. These resins were coated onto the stainless steel panels and tested for their gloss, cross-hatch adhesion, falling weight impact resistance, flexibility, abrasion, scratch hardness, solvent scrub resistance, and chemical resistance. The thermo-mechanical properties of these coatings were determined by TGA, DSC, DMTA, and tensile strength measurements. The cryofractured specimens were subjected to SEM analysis. The influence of structural differences of two flexibilizers on the coating properties was investigated. These coatings exhibited excellent properties and have great potential in industrial applications.

“…The peaks at 912 cm −1 and 845 cm −1 for neat PPGEF resin correspond to the oxirane rings . Similar peaks also appear in spectra of all the cardolites.…”

Section: Resultssupporting

confidence: 58%

Flexible epoxy novolac coatings: Use of cardanol‐based flexibilizers

Gour

Raut

Badiger

2017

“…Abrasion resistance was tested by LFY‐109B fiber abrasion tester (Shandong Textile Academy, China) . Fluffs and breakage was measured according to Japanese patent .…”

Section: Methodsmentioning

confidence: 99%

Microstructure and properties of carbon fiber sized with pickering emulsion based on graphene oxide sheets and its composite with epoxy resin

Wang

Liu

et al. 2015

Self Cite

The Graphene oxide (GO) sheets were used for preparing the epoxy resin Pickering emulsion. The particle size and the zeta potential of the Pickering emulsion were measured to evaluate its stability. The stable emulsion could be served as the film former of sizing agent for carbon fiber (CF). The effect of the Pickering emulsion stabilized by GO sheets on the properties of CF and the interfacial adhesion property of CF reinforced composite were investigated. Scanning electron microscopy (SEM) images showed that there existed a layer of sizing agent film with GO sheets evenly on the CF surface. Abrasion resistance and stiffness values of CF were tested and the results indicated that the sized CF conformed to the requirement of CF handleability. The interlaminar shear strength (ILSS) test indicated that the interfacial adhesion of the composite could be greatly improved. The fracture surfaces of CF composites were examined by SEM after ILSS tests. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42285.

“…The FT‐IR spectra of neat PPGEF, Cardolite NC‐514, Cardolite NC‐547 along with cured epoxy novolac composites containing different amounts of cardolites are shown in Figure (a,b). The neat PPGEF resin showed characteristic peaks at 912 and 845 cm −1 , which correspond to the oxirane rings . These oxirane ring peaks also appeared in neat Cardolite samples.…”

Section: Resultsmentioning

confidence: 94%

Toughening of epoxy novolac resin using cardanol based flexibilizers

Gour

Kodgire

Badiger

2015

In this work, two different cardanol based epoxies (Cardolite NC‐514 and Cardanol NC‐547) were employed as flexibilizers to toughen an epoxy novolac resin namely, poly[(phenylglycidyl ether)‐co‐formaldehyde] (PPGEF). 4,4′‐Diamino‐3,3′‐dimethyl dicyclohexyl methane (BMCHA) was used as a curing agent. Differential scanning calorimetry and dynamic mechanical thermal analysis of the composites showed a gradual decrease in glass transition temperatures (Tg) with increase in cardolite content confirming the incorporation of flexible moieties into the brittle resin matrix. Improvement in toughening of PPGEF/Cardolite composites was manifested by increase in the izod impact strength of both the composites. The tensile strength increased marginally for composites with increasing amount of Cardolite NC‐514 but decreased for the composites containing Cardolite NC‐547. This was attributed to the lack of rotational motion in the chain due to close proximity of rigid phenyl rings in NC‐547. SEM of the cryo‐fractured surfaces of composites showed good compatibility between PPGEF and cardanol based flexibilizers. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43318.