Methods for microwave melting of fiber mixtures to form composite materials include placing the fiber mixture in a receptacle located in a microwave oven. The methods further include microwave heating the mixture, causing a heat activated compression mechanism to automatically increase compressive force on the mixture, thereby eliminating air and void volumes. The heat activated compression mechanism can include a shape memory alloy wire connecting first and second compression brackets, or one or more ceramic blocks configured to increase in volume and thereby increase compression on the mixture.

A pressing machine that applies heat and pressure to a press object transported in a first direction includes a first die having a first heater, a second die having a second heater and being disposed above the first die, a support member that supports the first die and the second die, and a movement mechanism that moves the support member from a first position to a second position located in a second direction intersecting the first direction from the first position, in which the first position is the position at which the first die and the second die apply heat and pressure to the press object and the second position is the position at which the first die and the second die do not face the press object.

An addition reaction type polyimide resin molded body having a thickness of 5 mm or more, with a number of defects having a size of 0.5 mm or more present on the entire surface of the molded body being 1 per 100 cm.sup.2 or less. The addition reaction type polyimide resin molded body is formed by: holding a prepolymer of an addition reaction type polyimide resin at a temperature equal to or higher than a viscosity increase starting temperature of the addition reaction type polyimide resin and increasing a melt viscosity at a temperature lower by 10° C. than the viscosity increase starting temperature to 70 to 900 kPa.Math.s; grinding and mixing the addition reaction type polyimide resin to form a molding precursor; and shaping the molding precursor at a temperature equal to or higher than a heat-curing temperature of the addition reaction type polyimide resin.

Process and relative machine for moulding a thermoplastic material for producing a finished article having a shape, wherein the process comprises: providing a mould (99) comprising a first (1) and a second half-mould (2) each having a respective conformation surface (3, 4) which define, with closed mould, a cavity (5) having, in a conformation configuration, the shape; making a semi-finished product (70) made of the thermoplastic material; closing the mould (99) with the semi-finished product (70) interposed between the conformation surfaces (3, 4); admitting a heating fluid into the cavity (5) for heating the semi-finished product (70) permeable to the heating fluid; arranging the cavity (5) in a compacting configuration in which the cavity (5) coincides with a sub-portion of the cavity (5) in the conformation configuration; with the cavity (5) in the compacting configuration and the heating fluid into the cavity (5), compressing the semi-finished product (70) between the conformation surfaces (3, 4); subsequently to compressing the semi-finished product (70), arranging the cavity (5) in the conformation configuration while keeping the heating fluid into the cavity (5), wherein the semi-finished product (70) elastically expands for completely occupying the cavity and assuming the shape; subsequently, evacuating the heating fluid from the cavity (5) for cooling the semi-finished product (70) for obtaining the finished article with the shape; opening the mould (99) and extracting the finished article from the mould (99).

Process and relative machine for moulding a thermoplastic material for producing a finished article having a shape, wherein the process comprises: providing a mould (99) comprising a first (1) and a second half-mould (2) each having a respective conformation surface (3, 4) which define, with closed mould, a cavity (5) having, in a conformation configuration, the shape; making a semi-finished product (70) made of the thermoplastic material; closing the mould (99) with the semi-finished product (70) interposed between the conformation surfaces (3, 4); admitting a heating fluid into the cavity (5) for heating the semi-finished product (70) permeable to the heating fluid; arranging the cavity (5) in a compacting configuration in which the cavity (5) coincides with a sub-portion of the cavity (5) in the conformation configuration; with the cavity (5) in the compacting configuration and the heating fluid into the cavity (5), compressing the semi-finished product (70) between the conformation surfaces (3, 4); subsequently to compressing the semi-finished product (70), arranging the cavity (5) in the conformation configuration while keeping the heating fluid into the cavity (5), wherein the semi-finished product (70) elastically expands for completely occupying the cavity and assuming the shape; subsequently, evacuating the heating fluid from the cavity (5) for cooling the semi-finished product (70) for obtaining the finished article with the shape; opening the mould (99) and extracting the finished article from the mould (99).

A method for obtaining and applying a sealing gasket element on a slide-valve sliding in a cavity of an apparatus for the recirculation and mixing of chemically reactive polymeric components, comprises the steps of: obtaining from an elastic-plastic material a precursor element of the seal element, with a grid structure having a reticular shape; positioning the precursor element around the slide-valve; exerting on the precursor element, through temporary clamping elements, a radial compression and contraction action to insert it and couple it to one or more housing seats provided on the slide-valve so as to obtain the seal element well coupled to the latter; progressively removing the clamping elements to sequentially release successive parts of the gasket element and gradually free the slide-valve to gradually introduce the parts of the slide-valve—freed in succession—in the housing cavity allowing the sealing gasket element to gradually expand radially due to the elastic return by adhering tightly to the inner surface of the same housing cavity. The special equipment for fitting the sealing gasket element on the slide-valve and the so obtained recirculation and mixing apparatus is also described.

A method for producing a part in the form of a solid block from a natural material in particulate form containing scleroproteins. A phase of heating the natural material, under compression at a pressure greater than or equal to 30 MPa, to a temperature greater than or equal to the denaturation temperature of the scleroproteins contained in the material. A phase of cooling the material thus obtained to a temperature less than 100° C., while maintaining the compression during at least a part of the cooling phase.

A method for producing a part in the form of a solid block from a natural material in particulate form containing scleroproteins. A phase of heating the natural material, under compression at a pressure greater than or equal to 30 MPa, to a temperature greater than or equal to the denaturation temperature of the scleroproteins contained in the material. A phase of cooling the material thus obtained to a temperature less than 100° C., while maintaining the compression during at least a part of the cooling phase.

A method for producing a press-molded body of a polycarbonate sheet including resin layers (A) and (B) respectively containing a polycarbonate resin, and a high hardness resin (B) and a hard coat layer (C) sequentially stacked on at least one surface of the resin layer (A). The method includes pre-heating the polycarbonate sheet to a temperature between a glass transition point of the resin layer (A)−45° C. or higher and the glass transition point or lower; locating the pre-heated polycarbonate sheet between an upper and lower die of a mold, wherein a time period after the pre-heating is finished until the polycarbonate sheet is located between the upper and lower die of the mold is 90 seconds or shorter; and clamping the mold to press the upper and lower die to obtain the press-molded body of the polycarbonate sheet.

A method for producing a press-molded body of a polycarbonate sheet including resin layers (A) and (B) respectively containing a polycarbonate resin, and a high hardness resin (B) and a hard coat layer (C) sequentially stacked on at least one surface of the resin layer (A). The method includes pre-heating the polycarbonate sheet to a temperature between a glass transition point of the resin layer (A)−45° C. or higher and the glass transition point or lower; locating the pre-heated polycarbonate sheet between an upper and lower die of a mold, wherein a time period after the pre-heating is finished until the polycarbonate sheet is located between the upper and lower die of the mold is 90 seconds or shorter; and clamping the mold to press the upper and lower die to obtain the press-molded body of the polycarbonate sheet.