Controlled release of compounds utilizing a plastic matrix

A controlled release pesticide dispenser, comprising:

• a polymer, an aquatic pesticide, and a porosity inducing agent,
• said polymer in the form of a matrix and containing said aquatic pesticide and said porosity inducing agent,
• the amount of said polymer being 100 parts by weight, said polymer selected from the group consisting of a thermoplastic polymer, a thermoset polymer, and combinations thereof,
• said aquatic pesticide being a pesticide for destorying animal aquatic pests in an aqueous environment, the amount of said pesticide ranging from about 2 parts to about 80 parts by weight per 100 parts of said polymer, except when said pesticide is an organotin compound, the amount of said organotin compound ranging from about 25 to about 75 parts, and
• said aquatic pesticide slowly being released from the dispenser, and porosity agent having a solubility of 100 grams or less per 100 grams of water.

A method for preparing a slow release pesticide dispenser, comprising the steps of:

• adding and mixing 100 parts by weight of a polymer, an aquatic pesticide for use in an aqueous environment for destroying aquatic pests, and a porosity inducing agent having a solubility of 100 grams or less per 100 grams of water, the amount of said pesticide ranging from about 2 parts to about 80 parts by weight per 100 parts of said polymer, except wherein said pesticide is an organotin compound, the amount of said organotin compound ranging from about 25 parts to about 75 parts by weight per 100 parts of said polymer;
• and
• forming a polymer matrix dispenser so that upon contact with an aqueous environment, said pesticide is slowly released therefrom.
• said polymer selected from the class consisting of a thermoplastic and a thermoset.

A method for the controlled release of pesticides from a floating dispenser into an aquatic environment, comprising:

• (a) dispersing a floating matrix into the environment, said matrix comprising a polymer, an aquatic pesticide for destroying aquatic pests, and a porosity inducing agent,
• said polymer selected from the group consisting of a thermoplastic polymer and a thermoset polymer;
• (b) dissolving said porosity agent from said matrix at a controlled rate upon contact with water, to create a pore structure in said matrix;
• (c) dislodging said aquatic pesticide through said pore structure from said matrix upon contact with water, said pesticide to retard or destroy undesired pests;
• said porosity agent having a water solubility less than 100 grams per 100 grams of water and said polymer being water insoluble and non-porous;
• said dispenser having a density of less than 1.0 grams per cc;
• and
• an anchor, said anchor having a density of greater than 1.0 grams per cc and connected to said dispenser.

A composition for destroying aquatic pests, comprising:

• a mixture of an aquatic pesticidally effective active ingredient which is water dispersible and an inert particulate material having a water solubility from less than 100 grams per 100 grams of water at 25.degree. C.;
• said mixture being dispersed within a water insoluble, non-porous polymer matrix, and being floatable;
• said polymer selected from the group consisting of a thermoplastic and a thermoset,
• the proportion of particulate material being sufficient to induce liquid porosity in said matrix upon exposure to water;
• and
• an anchor, said anchor connected to said floatable mixture.

A method for the controlled release of pesticides in an environment, comprising:

• (a) dispersing a matrix into the environment, said matrix comprising an aquatic pesticide for destroying pests, and a porosity inducing agent, said polymer selected from the group consisting of a thermoplastic and a thermoset;
• (b) dissolving said porosity agent from said matrix at a controlled rate upon contact with water, to create a pore structure in said matrix;
• (c) dislodging said aquatic pesticide through said pore structure from said matrix upon contact with water, said pesticide to retard or destroy undesired pests;
• and
• said porosity agent having a water solubility less than 100 grams per 100 grams of water and said polymer being water insoluble and non-porous.