A multilayer structure selected from a reservoir, a pipe or a tube, for transporting, distributing or storing hydrogen, including, from the inside to the outside, at least one sealing layer and at least one composite reinforcing layer, the innermost composite reinforcing layer being welded to the outermost adjacent sealing layer, the sealing layers including at least one semi-crystalline thermoplastic polymer, the Tm of which is less than 280° C., wherein the at least one thermoplastic polymer of each sealing layer may be the same or different, and at least one of the composite reinforcing layers being of a fibrous material in the form of continuous fibers impregnated with a composition of at least one thermoplastic polymer P2j, the thermoplastic polymer P2j having a Tg greater than the maximum temperature of use of said structure (Tu), with Tg≥Tu+20° C., Tu being greater than 50° C.

A method of making an aircraft blade is provided. The method comprises the steps of: assembling two or more fibre-reinforced thermoplastic composite parts into a blade assembly; and welding the fibre-reinforced thermoplastic composite parts together utilising an additional thermoplastic located at least at locations where the parts will abut when assembled. The additional thermoplastic has a melting or softening temperature lower than a melting temperature of each of the fibre-reinforced thermoplastic composite parts being assembled. The step of welding comprises heating the blade assembly to a temperature above the melting/softening temperature of the additional thermoplastic and below the melting temperature of each of the fibre-reinforced thermoplastic composite parts so as to melt/soften the additional thermoplastic and thereby weld the fibre-reinforced thermoplastic composite parts together to form the aircraft blade.

The present disclosure provides a welded body having a connecting structure formed by welding a first molded body and a second molded body, wherein the first and second molded bodies contain at least one copolymer selected from the group consisting of a tetrafluoroethylene/fluoro(alkyl vinyl ether) copolymer and a tetrafluoroethylene/hexafluoropropylene copolymer, and wherein the connecting structure has a liquid contact surface to be in contact with a liquid having a solubility parameter of 14 to 35 (MPa).sup.1/2, a welded part formed in the connecting structure is not exposed to the liquid contact surface, and the number of particles of 30 nm or larger to be eluted from the liquid contact surface in the connecting structure is 1,000 particles/ml or less.

Provided are a method for producing a thermoplastic liquid crystal polymer (TLCP) film having an improved thermo-adhesive property, a circuit board, and a method for producing the same. The production method of the TLCP film includes preparing a TLCP film as the adherend film and a TLCP film as the adhesive film;

examining each of the prepared TLCP films for a relative intensity calculated as a ratio in percentage of a sum of peak areas of C—O bond peak and COO bond peak based on the total area of C1s peaks in the XPS spectral profile so as to calculate a relative intensity X (%) as for the prepared adherend film and a relative intensity Y (%) as for the prepared adhesive film; and

controlling the TLCP film as the adhesive film to have a relative intensity Y by selection or activation treatment of the adhesive film so that the relative intensity X of the adherend film and the relative intensity Y of the controlled adhesive film satisfy the following formulae (1) and (2):

38<X+Y<65   (1)

−8.0<Y−X<8.0   (2).

A method of producing flexible polypropylene fabric bags with heat fused seams comprising providing fabric pieces, wherein each fabric piece has a coated side and an uncoated side; positioning fabric pieces so that a coated side of one fabric piece faces a coated side of another fabric piece; selecting an area of fabric to be joined for forming a seam or joint; applying heat to the area to be joined that is less than the melting point of the fabrics, for forming one or more seams or joints and wherein the heat fused seams or joints of a resulting polypropylene bag retains at least 85% of the fabric strength without using sewing machines.

A packaging machine including a hot plate assembly adapted to fuse a length of heat-sensitive film wrapped around a package. A controller is adapted to calculate a time period the heating element is energized to fuse the length of heat-sensitive film wrapped around the package based on an initial temperature of the heating element. A hot plate status indicator is adapted to indicate at least to different statuses of operation of the packaging machine.

The present disclosure is concerned with a method of forming a seal with a polyethylene based film structure. The polyethylene based film structure has at least one layer formed with an oriented polyethylene having a predetermined melting temperature (T.sub.m). A conductive heat sealing device provides heat to form the seal, where a first sealing bar of the conductive heat sealing device operates at a first operating temperature of at least 10 degrees Celsius (° C.) below the T.sub.m of the oriented polyethylene in the polyethylene based film structure and a second sealing bar of the conductive heat sealing device operates at a second operating temperature of at least 15° C. higher than the operating temperature of the first sealing bar. The seal formed with the polyethylene based film structure retains at least 99 percent of its original surface area prior to forming the seal.

A method for connecting two components. In this method, a first component and a second component, which are each formed from a thermoplastic material, are first provided. The first component has a first peel-off ply on a first surface of the first component. The first peel-off ply is removed from the first component. Once the first peel-off ply has been removed, the first surface of the first component is brought into contact with a second surface of the second component. The first component and the second component are then welded to one another at the first and second surface by ultrasonic welding.

A flat strip 1, suitable for forming a tube flexible skirt, comprising a decorative film 15 superimposed on a primary film 16, said primary film 16 consisting of a series of polymeric layers and comprising a sealable inner layer 14 at the lower surface 20 of the strip 1, said decorative film 15 comprising a sealable outer layer 7 at the upper surface 19 of the strip 1 and a decorative layer 8, 9.

The primary film 16 comprises means for stabilizing the strip 1 and protecting the decorative layer 8, 9 against heating.

Aspects of the disclosure relate to manufacturing a balloon envelope for use in a stratospheric balloon system. For instance, a stream of polyethylene mixture us extruded through an extruder in order to orient molecules of polymer chains of polyethylene and to provide an oriented film. The oriented film is passed through an electron beam and thereby crosslinking the polymer chains to provide a cross-linked film. The cross-linked film is heat sealed to form the balloon envelope.