Reduction of formaldehyde emission from plywood using composite resin composed of resorcinol–formaldehyde and urea-modified scallop shell nanoparticles

Abstract

More than 200,000 tons of scallop shells are disposed annually alone in Japan. 1 Nanoparticles derived from scallop shells have the potential to adsorb gaseous 2 formaldehyde; therefore such discarded shells have now been tested as additive filler in 3 plywood adhesive by mixing high specific surface area, urea-modified shell nanoparticles 4 with a resorcinol-formaldehyde resin; with this procedure it was found that the emission of 5 formaldehyde from the resulting plywood could be substantially reduced. The 6 urea-modified scallop shell nanoparticles were prepared by two different methods: (i) by a 7 dry method in which the shells were treated with planetary ball-grinding under ambient 8 conditions -a completely dried powder was obtained after addition of the 9 surface-modifying urea solution; (ii) by a moist method by treating dry-ground shell 10 particles in a wet grinding process with the urea solution, followed by the use of 11 centrifugation to obtain a paste. The specific surface area of the nanoparticles obtained by 12 both treatments was 42 ± 3 m 2 /g. Measurement of the subsequent formaldehyde emission 13showed that the addition of the modified scallop shell nanoparticles substantially reduced 14 the formaldehyde emission from plywood; the reduction depends from the specific mass 15 uptake of urea on the nanoparticles which especially was the case when resins containing 16 nanoparticles processed by the moist method were used. 17 18

Green Preparation of Straw Fiber Reinforced Hydrolyzed Soy Protein Isolate/Urea/Formaldehyde Composites for Biocomposite Flower Pots Application

“…However, with increasing concern about environmental pollutants produced from the formaldehyde of the U/F resin, researchers have focused on environmentally friendly polymers for reducing the amount of formaldehyde. Lots of effort has been taken to reduce formadehyde emissions by adding compounds into U/F, including core flour [ 23 , 24 ], glycolysis products [ 25 ], scallop shell nanoparticles [ 26 ], nano SiO 2 [ 27 , 28 , 29 ], nanocrystalline cellulose [ 30 ], and corn flour [ 31 ].…”

Reduction of formaldehyde emission from urea-formaldehyde resin with a small quantity of graphene oxide

“…Previously we investigated the reduction of the formaldehyde emission from a UF/natural scavenger (scallop shell nanoparticles, main component was calcium carbonate). 51 To reduce the emission, the contained particles should be over 80 wt% of the total weight of the solid content of UF resin and the scavenger ( Table 1 ). Herein a graphite amount of 1.9 wt% or less was insufficient to prevent formaldehyde emission.…”

Urea impregnated multiwalled carbon nanotubes; a formaldehyde scavenger for urea formaldehyde adhesives and medium density fiberboards bonded with them

“…There are some interesting reports on using nanomaterials in UF adhesive to reduce formaldehyde release from the final products, that is, MDFs 27–31 . Cademartori et al reported alumina nanoparticles as a novel formaldehyde scavenger for UF resin.…”