Cured epoxies recycling

For polyamine-cured resin, recycle of presoaked epoxy also increased both impact strength and heat deflection temperature. For polyamide-cured resin, recycle also increased volume resistivity. Pre-soaked recycle dramatically increased adhesion to aluminum, especially in the anhydride system. 

TRAN-BRUNI DEANIN Recycling of Cured Epoxy Resins... 

Thermosensitive hydrogels, 13 743 THERMOSET Thermoset recycling pyramid, 13 780-781 Thermoset elastomers, 20 71 Thermoset epoxy resins, curing of, 10 421 Thermoset flexible polyurethane foams properties of, 25 461 Thermoset matrix composites, 21 456 Thermo set molding properties of diallyl isophthalate, 2 262t Thermoset polymers, 25 455 cured, 10 425... 

Epoxy resin was cured with polyamine, polyamide, or anhydride ground to pass a 0.5-mm screen and 20 was recycled into the next batch of virgin resin, either directly or after pre-soaking in the liquid ingredients. When these "filled" resins were cured, hardness was generally higher than for virgin resins. 

In fact, RIM was the first plastic to be approved for bumper fascia in North America to meet the low-temperature crashworthiness demanded by some OEMs. Unfortunately, due to process complexity, RIM could not be fabricated at a high enough rate to meet the demands of large car platforms. Faster cycle time for part production is delimited by the speed of curing chemistry and the ability of the resin to flow into molds. Furthermore, the automotive industry wanted to move away from the use of thermoset polymer systems that cannot be remelted. This attribute of thermosets was labeled by the industry as non-recyclable, and the industry made room for other thermoplastics such as TPO that can be remelted. Reaction-injection-molded parts are made from urethane epoxies, polyesters, and polyamides. A study of cost versus performance reported that RIM gives the best cost-performance characteristic for composite materials and is competitive with steel. ... 

It has been shown that recycled FR-4 epoxy laminates are advantageous fillers for UPRs [58]. Moreover, caldiun carbonate and copper were used as additional fillers. The fillers affected the curing rate, decreased the flexural strength and increased the flexural modulus. The shredded laminates were used in the amount of 100 phr. 

Dang W., Kubouchi M., Yamamoto S., Sembokuya H. and Tsuda K. (2002), An approach to chemical recycling of epoxy resin cured with amine using nitric acid. Polymer, 43, 2953-8. 

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