The invention relates to a process for manufacturing a copolymer foam containing polyamide blocks and polyether blocks, comprising the following steps: mixing the copolymer melt with a blowing agent, said copolymer having a coefficient of thermal diffusivity a and a crystallization temperature T.sub.c; providing a mold of thickness h at a temperature T.sub.m; injecting the mixture of the copolymer and of the blowing agent at a temperature T.sub.p, into the closed mold; foaming the mixture by opening the mold;
in which the maintenance time between the injection of the mixture of the copolymer and of the blowing agent into the closed mold and the opening of the mold is within the range extending from (t.sub.opt−25%) to (t.sub.opt+25%),
t.sub.opt being expressed in seconds and obtained by equation (I):

[00001]$\begin{array}{cc}{t}_{\mathrm{opt}}=-\frac{1}{{\pi }^2}\frac{h^2}{a}\ln \left(\frac{\pi }{4}\frac{T_m-T_c}{T_m-T_p}\right),& \left(I\right)\end{array}$

in which a is expressed in m.sup.2/s, h is expressed in m and T.sub.m, T.sub.c and T.sub.p are expressed in ° C.

A vehicle PU composite component having a layered construction having a honeycomb structure, the honeycomb structure being reinforced by PU material, and the layered construction or the component being formed from PU material and having at least one component elevation. The component elevation PU material forming the component elevation differs from the honeycomb structure PU material reinforcing the honeycomb structure, and in that the component elevation PU material has a higher foaming degree having lower material density as compared to the honeycomb structure PU material. A method for producing a vehicle PU composite component having a layered construction having a honeycomb structure.

A structure includes a skin and a foam member. The foam member has a molded contour, the mold contour being configured to provide tooled surface for the skin. When the skin is a composite skin, the foam member provides support for the skin so that the skin can be cured under heat and pressure. A method of making the foam member for a foam stiffened structure includes creating a mold having an interior cavity which resembles a desired shape the foam member. A subsequent step involves introducing a foam mixture into the mold. Next, the foam mixture is allowed to polymerize so as to expand and distribute within the cavity of the mold. The method further includes selectively controlling a density of the foam member in the mold. The foam member is at least partially cured. The foam member is assembled with a skin to produce the foam stiffened structure.

A method for manufacturing a composite structure in which a first member and a structure material as a second member are integrated, the method including: an arrangement step of arranging a structure precursor including a resin and reinforced fibers in a mold made of the first member; a heating step of heating the structure precursor to equal to or higher than a temperature at which a storage elastic modulus (G′) of the structure precursor is less than 1.2×10.sup.8 Pa; a shaping step of expanding the structure precursor by heating to form a structure material as a second member, and bringing the structure material into close contact with the first member to obtain a composite structure; and a cooling step of cooling the composite structure.

A method for manufacturing a composite structure in which a first member and a structure material as a second member are integrated, the method including: an arrangement step of arranging a structure precursor including a resin and reinforced fibers in a mold made of the first member; a heating step of heating the structure precursor to equal to or higher than a temperature at which a storage elastic modulus (G′) of the structure precursor is less than 1.2×10.sup.8 Pa; a shaping step of expanding the structure precursor by heating to form a structure material as a second member, and bringing the structure material into close contact with the first member to obtain a composite structure; and a cooling step of cooling the composite structure.

A structural member (10) comprising: (i) a pultruded secondary member (14) including a first surface and an opposing second surface; and (ii) a molded carrier (12) overmolded onto at least one of the first and second surface of the pultruded secondary member, the molded carrier including a plurality of ribs (16); wherein the secondary member and the carrier are dissimilar materials.

A push-in earplug including an elongate core and outer layer is disclosed. The outer layer includes a sound attenuating portion having a first average density and a stem portion having a second average density, and the second average density is greater than the first average density.

A push-in earplug including an elongate core and outer layer is disclosed. The outer layer includes a sound attenuating portion having a first average density and a stem portion having a second average density, and the second average density is greater than the first average density.

A system and method to dispense, mix, and inject liquids and force them into a vented investment pattern mold cavity comprises a source of raw materials in fluid communication with an injection unit for metering and delivering the raw materials. A mixing and injection head receives and mixes the metered raw materials. A movable molding cart upon which an investment pattern mold is mounted is disposed adjacent the injection unit and proximate the mixing and injection head. The movable molding cart includes a fill cup that may be engaged by the mixing and injection head. A displaceable gating tray provides fluid communication with the fill cup and a sprue aligned with an investment port on a lower portion of the investment pattern mold. The system also includes a digital computer control by which the injection process may be controlled.

A system and method to dispense, mix, and inject liquids and force them into a vented investment pattern mold cavity comprises a source of raw materials in fluid communication with an injection unit for metering and delivering the raw materials. A mixing and injection head receives and mixes the metered raw materials. A movable molding cart upon which an investment pattern mold is mounted is disposed adjacent the injection unit and proximate the mixing and injection head. The movable molding cart includes a fill cup that may be engaged by the mixing and injection head. A displaceable gating tray provides fluid communication with the fill cup and a sprue aligned with an investment port on a lower portion of the investment pattern mold. The system also includes a digital computer control by which the injection process may be controlled.