Patent ID: 7335374

Claim:
A method of making a multi-layer barrier for preventing wood pests from accessing a wooden structure for a prolonged period of time and with a minimal impact on the environment, the method comprising: forming a first layer comprising a first polymer, a pesticide in liquid, and a carrier by binding the pesticide to the carrier to form a pesticide-carrier mixture, the pesticide selected from isofenphos, fenvalerate, cypermethrin, permethrin, tefluthrin, lambdacyhalothrin, cyfluthrin, deltamethrin, and combinations thereof and the carrier is selected from carbon black, activated carbon, alumina, silicoaluminate, hydroxyapatite and combinations thereof, mixing the first polymer and the pesticide-carrier mixture to form a mixture, the first polymer is selected from high density polyethylene, low density polyethylene, ethylene vinyl acetate, vinyl acetate, urethane, polyester, a thermoplastic elastomer, silicone, neoprene, polyethylene, polyurethane, polypropylene, polybutylene, epoxy polymers, polyamides, acrylate-styrene-acrylonitrile, aromatic polyesters, unsaturated polyesters, polyisoprene, and combinations thereof, melting the mixture, and solidifying the mixture to form a polymer matrix, the pesticide-carrier mixture bound within the polymer matrix of the first layer, the first layer being permeable to the pesticide; and combining the first layer with a second layer, the second layer comprising a second polymer, the second layer being substantially non-releasing and impermeable in that the pesticide is released from the barrier at a rate of less than 0.4 μg/cm 2 /day, the release rate being sufficient to prevent wood pests from breaching the barrier.