Abstract: Process for making a tow pre-preg (or tow-preg) comprising long continuous fibers coated with a thermoplastic polymer. A spread tow of long continuous fibers, preferably carbon or glass, is grounded and coated with electrostatically charged particles. The fiber diameter is about 5-50 microns and the mean particle diameter is about 0.1-40 microns. A particle laden air stream is formed by aspirating fluidized polymer particles into a flowing air stream whose velocity exceeds the settling velocity of the particles. The particles in the flowing air stream are continuously electrostatically charged by means of an applied voltage of at least about 20 kV. The flowing air stream with electrostatically charged particles suspended therein is then contacted with the continuously moving grounded spread fiber tow. The particle laden air stream is flowing downwardly and the fiber tow moving horizontally at the time of contact.

Abstract: Process for making a tow pre-preg comprising long continuous fibers coated with a thermoplastic polymer. A continuously moving spread tow of long continuous fibers, preferably carbon or glass, is humidified in an atmosphere of essentially 100% relative humidity and coated with particles of a thermoplastic polymer. A polymer particle-laden air stream contacts the moistened continuously moving tow, depositing polymer particles on the fibers. The fiber diameter is about 5-50 microns and the mean particle diameter is about 0.1-40 microns. The fibers with thermoplastic particles clinging thereto are continuously heated to a temperature sufficient to cause fusion of the thermoplastic polymer. This results in long continuous fibers coated with the thermoplastic polymer. The resulting tow-preg, or tow of coated fibers, is useful in the preparation of structural composites in which the fibers service reinforcing fibers.

Abstract: An extrusion head for a blow molding machine wherein a movable plunger is slidably mounted in a distributor head which receives a melt at an inlet end of its channel and directs it along such channel to the terminal end of the channel while simultaneously directing portions of it along spiral radial paths to the lower circumferential edge of the distributor head to fill an accumulator chamber which also causes the plunger to recede facilitating the filling of the accumulator chamber. The channel as defined by the adjacent circumferential wall and the curvilinear contour on the distributor head defines a smooth integral flow channel that is curvilinear in cross section.

Abstract: A process for producing shaped or molded articles made of polymer particles containing aromatic imide linkages includes the steps of introducing the polymer particles into a chamber for heating the particles, the chamber having a blade which rotates in the chamber and heats the particles by impacting them; heating the polymer particles to a forming temperature; discharging the polymer particles into a shaping device, such as a mold; and, pressurizing the polymer in the shaping device until the polymer particles consolidate into the shape desired. The process has proven to be effective with polymers that are difficult to process, such as thermoplastic polyimide polymers, polyetherimide polymers, bismaleimide polymers, polyarylate polymers, amideimide polymers, and other polymers containing fully reacted aromatic imide linkages.

Abstract: An extrusion head for a blow molding machine wherein a movable plunger is slidably mounted in a distributor head which receives a melt at an inlet end of its channel and directs it along such channel to the terminal end of the channel while simultaneously directing portions of it along spiral radial paths to the lower circumferential edge of the distributor head to fill an accumulator chamber which also causes the plunger to recede facilitating the filling of the accumulator chamber. The channel as defined by the adjacent circumferential wall and the curvilinear contour on the distributor head defines a smooth integral flow channel that is curvilinear in cross section.

Abstract: Foamed thermopolastic resin comprising poly (p-methylenebenzoate) suitable for structural foam injection molded parts.

Abstract: Foamed thermoplastic resin comprising poly(p-methylenebenzoate) suitable for structural foam injection molded parts.

Abstract: A process for the production of foamed products from an unsaturated polyester resin composition, said composition comprising polyester resin, unsaturated monomer, a promotor, initiator, physical blowing agent, and compatible surfactant whereby a known gel time "T" results, foaming said composition by exposing it to microwave radiation prior to 1 T, thereafter permitting said foam structure to exotherm to obtain a fully cured product. Preferably the resin composition is exposed to the radiation between 0.2 and 0.7 T. Due to the foamed nature of these products, they will find many uses where insulation and light weight is important. End products include foamed unsaturated polyester resins and products incorporating the same such as patio blocks containing a polyester gel-coat, the gel-coat containing sand, decorative chips, or other decorative aggregate. The foam is a mixture of polyester resin and fillers and has a density of about 35 pounds per cubic foot.

Abstract: A process for producing shaped articles of polyalkylene terephthalate resins involves thermoforming a substantially unoriented sheet of said resin which sheet has an average crystallinity thermally induced in the range of about 0% to 18% and an average temperature in the range of about 210.degree.-300.degree. F., in contact with a mold at a temperature in the range of about 240.degree.-350.degree. F. which mold is preferably at a higher temperature than said sheet. Optionally a differential in applied pressure below about 5 atmospheres can be utilized in the thermoforming.