Abstract: The present invention is directed to a piezoelectric transformer based power converter that exhibits efficient operating point tracking ability while providing output regulation by means of simultaneous two-parameter control of the converter power stage. A regulation control stage provides the power stage a regulation control signal indicative of the difference between the measured output parameter and a set-point reference, therefore continuously controlling the gain of the converter to result in a stabilized, regulated output. Additionally, a frequency control stage simultaneously provides the power stage with a frequency control signal correlative to the difference between the current and desired operating points of the piezoelectric transformer. The power stage then translates the frequency control signal into an adjustment to the operational frequency of the input signal to the piezoelectric transformer, as to continuously drive the operating point to the desired position.

Abstract: A uniformly premixed sealant is extruded into a packaging form and allowed to pressure equilibrate prior to freezing. Upon warming the sealant begins to cure. The storage of the preformed sealant formulation under cold conditions arrests the activity of cure catalysts and accelerators mixed therethrough. The sealant is readily extruded into a preform shape containing a lightweight filler. A release film is provided to avoid contact with the sealant preformed in a shape during application to a substrate.

Abstract: A uniformly premixed sealant is extruded into a packaging form and allowed to pressure equilibrate prior to freezing. Upon warming the sealant begins to cure. The storage of the preformed sealant formulation under cold conditions arrests the activity of cure catalysts and accelerators mixed therethrough. The sealant is readily extruded into a preform shape containing a lightweight filler. A release film is provided to avoid contact with the sealant preformed in a shape during application to a substrate.

Abstract: A method and composition for decreasing the viscosity of mercaptan terminated polymers. The method involves adding thiol terminated trithio-orthoformate polycondensates to the mercaptan terminated polymer to achieve desired decreases in viscosities without adversely affecting other physical properties. The polycondensates have the formula(HS--R--S--).sub.2 CH--S--R'--S[--CH(--S--R"--S).sub.2 --].sub.n (H).sub.xwherein R, R', and R" are alkylene, arylene, alkylene thioether, or alkylene ether, either the same or different; n is 0-10; and x is n+1.