Effect of the hottest diluent on composite quality

2022-07-23
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The effect of diluent on composite quality

the two-component adhesive for dry composite must be diluted with solvent in order to apply evenly and facilitate infiltration

the main solvents are ethyl acetate, toluene, methyl ethyl ketone, etc. many factors should be considered when selecting solvents. Because toluene is toxic, it is difficult to dry, and it is easy to produce residual components. However, methyl ethyl ketone has a heavy smell and high price, Therefore, generally use B "These media have long had ethyl esters abroad. Their purity is required to reach 99% and their moisture content is 0.2%. Because -n=c=o system in the curing agent accumulates and its double bonds are repaired manually, which is very active. It reacts with water to generate amines and release CO2.

the reaction consumes the curing agent, reducing the amount of the curing agent participating in the glue reaction. At the same time, it releases CO2, which makes the adhesive layer contain bubbles, which is extremely detrimental to the dry-type composite and often affects the surface quality Bond strength. Similarly, the normal use of glue will be affected by the reaction of isocyanate group with active hydrogen of hydroxyl containing compounds such as alcohols and polyols to produce carbamate and acyl wrist with organic acid (hydroxyl). Therefore, the diluent must be tested during the compounding process

there is a problem that must be clarified here. Some compounding manufacturers believe that adding more diluents can reduce costs. This view is an extremely wide error in the field of plastic granulator operation. Diluents only play a role in coating evenly and facilitating infiltration in the compounding process. The real bonding role is glue and curing agent. However, this technology will be exhibited at the npe2015 Exhibition in Orlando, Florida, USA, and the diluent has volatilized, As long as a certain amount of dry glue is applied, it is more economical to add less diluent

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