The present invention provides a protective coating for protecting a substrate from deleterious elements present in environments in which the substrates are deployed and methods and apparatus for deploying a PVC encasement with a longitudinal snap jacket of suitable length and girth to coat a pylon substrate or building girder and provide a filler within the snap jacket and around an encased pylon.

A pressure chamber is provided for a blown film extrusion apparatus having (i) a die head for extruding a tubular polymer bubble, and (ii) a cooling assembly down-stream of the die head for receiving the bubble and applying a cooling fluid to the bubble. The pressure chamber includes an upstream end wall sealed around the die head outlet, and extending outward from the seal; a side wall movable between a closed position for controlling air flow from a chamber volume surrounding the bubble to the atmosphere, and an open position for permitting air flow from the chamber volume to the atmosphere. The upstream end wall has an inlet for receiving air from an air supply, and an outlet in fluid communication with the inlet and configured to direct the air into the chamber volume to pressurize the chamber volume when the side wall is in the closed position.

A process for producing an ion exchange precursor resin membrane involves co-extruding an ion exchange precursor resin with an incompatible polymer to form a multilayer film having a layer of the ion exchange precursor resin supported on a layer of the incompatible polymer. The layer of incompatible polymer is then removed from the layer of ion exchange precursor resin to provide the ion exchange precursor resin membrane. The ion exchange precursor resin membrane may be converted to an ion exchange resin membrane by hydrolysis, and subsequent acidification if desired. Ion exchange resin membranes and ion exchange precursor resin membranes having a uniform thickness of 25 microns or less may be formed by the process.

A polyetheretherketone pipe of length greater than 250 meters and a residual stress of less than 5 MPa may be made using a calibrator device 2 which includes a cone shaped opening 6 arranged to receive a molten extruded pipe shaped polymer. Attached to the front member 4 is a vacuum plate 14a and successive vacuum plates 14b-14h are attached to one another to define an array of vacuum plates, the vacuum plates being arranged to allow a vacuum to be applied to a pipe precursor passing through opening 16. The vacuum plates 14 also include temperature control means for heating or cooling the plates and therefore heating or cooling a pipe precursor passing through the openings. With a vacuum applied to opening 6, 16 and heating/cooling the plates, an extruded hot plastics pipe is inserted into calibrator 2 via opening 6 and conveyed through opening 16 in plates 14, whereupon it is urged by the vacuum against the cylindrical surface defined by plates 14 to maintain its shape and the temperature of each plate is controlled to control the rate of cooling of the pipe precursor passing through. The pipe may be cooled at a relatively slow rate so that a pipe made from a relatively fast crystallising polymer crystalises and the crystallinity of the pipe along its extent and throughout its thickness is substantially constant.

A device and method for blowing and stretching a plastic film are provided. A first blow-expanding mechanism subjects a primitive plastic film made of PVC, PLA, or PET to extrusion at a temperature of 140° C.-180° C. and primary blow-expansion to form a volume in which the primitive plastic film has a lateral opening ratio of 1:1. Front-stage press rollers and middle-stage press rollers then subject the primitive plastic film to primary longitudinal press-flattening and pull-stretching, followed by heating and blow-expanding by the second blow-expansion mechanism at a temperature of 160° C.-220° C. and a pressure of 1.1-1.6 atm to achieve a volume in which the primitive plastic film has lateral opening ratio of at least 2:1, further followed by reduction of temperature to a temperature of 10° C.-20° C. for shape fixing to form a shaped plastic film. Finally, rear-stage press rollers subject the shaped plastic film to secondary longitudinal press-flattening and pull-stretching.

The present invention is directed to a method of incrementally stretching polymeric film formed from a blown film extrusion process. The present invention is further directed to a polymeric bag formed from an incrementally stretched polymeric film. The incremental stretching is performed on a collapsed polymeric bubble via a pair of intermeshing rollers. The incrementally stretched polymeric film may be stretched only along a portion of its width. The polymeric bag may be a drawstring trash bag with an extended hem where only the extended hem of the bag or the body of the bag comprises incrementally stretched polymeric film.

The present invention is directed to a method of incrementally stretching polymeric film formed from a blown film extrusion process. The present invention is further directed to a polymeric bag formed from an incrementally stretched polymeric film. The incremental stretching is performed on a collapsed polymeric bubble via a pair of intermeshing rollers. The incrementally stretched polymeric film may be stretched only along a portion of its width. The polymeric bag may be a drawstring trash bag with an extended hem where only the extended hem of the bag or the body of the bag comprises incrementally stretched polymeric film.

The present invention is directed to a method of incrementally stretching polymeric film formed from a blown film extrusion process. The present invention is further directed to a polymeric bag formed from an incrementally stretched polymeric film. The incremental stretching is performed on a collapsed polymeric bubble via a pair of intermeshing rollers. The incrementally stretched polymeric film may be stretched only along a portion of its width. The polymeric bag may be a drawstring trash bag with an extended hem where only the extended hem of the bag or the body of the bag comprises incrementally stretched polymeric film.

Systems and methods for generating a film suitable for medical packaging are provided. The film is generated by blown film co-extrusion to form a multi-layer film which has a heat resistant layer, a barrier layer and a heat seal layer. The barrier layer includes a high barrier resin and a branched co-polymer. The high barrier resin has a density of at least 0.963 g/cm.sup.3. The barrier layer includes between 25% and 85% high barrier resin. In some embodiments, an additional laminate layer may be affixed to the heat resistant layer of the multi-layer film. The final film is between 3.0 and 3.8 mils in thickness, and has a moisture vapor transmission rate of less than 0.08.

The present invention is directed to a method of incrementally stretching polymeric film formed from a blown film extrusion process. The present invention is further directed to a polymeric bag formed from an incrementally stretched polymeric film. The incremental stretching is performed on a collapsed polymeric bubble via a pair of intermeshing rollers. The incrementally stretched polymeric film may be stretched only along a portion of its width. The polymeric bag may be a drawstring trash bag with an extended hem where only the extended hem of the bag or the body of the bag comprises incrementally stretched polymeric film.