A method for preparing a rubber protective cover of an expressway guardrail includes steps of: (S1), preparing material, wherein the material includes high-temperature vulcanized rubber, nanometer zinc oxide, nanometer silicon dioxide and a modifier; (S2), placing the vulcanized rubber into a mixing furnace which is able to increase a temperature, and then heating to 200 C.; (S3), adding the nanometer zinc oxide, and then stirring for 10 minutes; (S4), adding the nanometer silicon dioxide, and then stirring for 5 minutes; (S5), adding the modifier, and then stirring for 30 minutes; and (S6), adding the rubber after stirring into a four-roll calender, shaping, and preparing the rubber cover having a thickness of 10-20 mm and a length of 300-600 mm. The present invention has a low cost, a corrosion resistance, an easy preparation process, a low equipment requirement and a strong operability.

There is provided a method of producing a bioactive polymer filament, the method comprising: providing a base polymer powder and a bioactive copolymer; mixing the base polymer powder with the bioactive copolymer to obtain a mixture; and extruding a bioactive polymer filament from the mixture at an extrusion temperature profile that is based on a predetermined melt/softening temperature and a predetermined onset degradation temperature of the bioactive polymer; and performing a post-extrusion thermal analysis on the extended bioactive polymer filament to assess onset degradation of the bioactive copolymer in the filament. There is also provided a bioactive polymer filament obtained from said method and a fused filament fabrication (FFF) or fused deposition modelling (FDM) based three-dimensional printing method.

Aspects of the present disclosure generally describe polyarylether ketones and methods of use. In some aspects, a composition includes one or more polymers of formulae (I), (II), or (III): ##STR00001##

The present invention is a phenolic resin foam board having a thickness of 40 mm or more to 300 mm or less, when the phenolic resin foam board is sliced into n pieces (n5) at approximately equal intervals of 8 mm or more to 10 mm or less, a density of an n-th specimen is d.sub.n, an average density of n pieces of specimens is d.sub.ave, a lowest density among the densities of n pieces of specimens is d.sub.min, 0(d.sub.aved.sub.min)/d.sub.ave0.12 is established, and when values for D.sub.i=(d.sub.i+d.sub.(i+1))/2 are calculated, D.sub.i values are plotted and points corresponding to the D.sub.i values are connected, resulting in a density distribution curve, no straight line parallel to the horizontal axis intersects the density distribution curve at four points.

A mold is provided. First and second materials are introduced into respective first and second portions of the mold to create a first and second parts of the item. The first and second parts of the item are allowed to solidify. The mold is opened and a heating element is inserted into the mold. A section of each of the first and second parts of the item is heated to above their glass transition temperatures with the heating element. The heating element is removed from the mold. The mold is closed such that the sections of the first and second parts of the item come into contact with each other. The sections of the first and second parts are cooled to below their glass transition temperatures to become joined. The mold is opened such that the item can be removed from the mold.

A polyarylene composition containing one or more polyarylenes and one or more sterically hindered phenolic stabilizers. The polyarylene composition has enhanced resistance to discoloration and degradation under thermal stress.

A system is described for reinforcing a thermoplastic workpiece including a subject surface and an underlying workpiece body volume. At least one substantially linear Z-pin having proximal and distal pin ends longitudinally separated by a pin body is provided. The proximal pin end is in direct contact with the subject surface. An ultrasonic energy source applies ultrasonic energy to the Z-pin to ultrasonically heat the Z-pin and thus locally melt the workpiece material of the subject surface and/or the workpiece body to create a melted workpiece material. The proximal pin end and at least a portion of the pin body of the Z-pin are penetrated into the melted workpiece material to create an inserted Z-pin length. The inserted Z-pin length is maintained in the workpiece body volume by solidified melted workpiece material around the inserted Z-pin length to reinforce the workpiece. A method of reinforcing a workpiece is also provided.

A system is described for reinforcing a thermoplastic workpiece including a subject surface and an underlying workpiece body volume. At least one substantially linear Z-pin having proximal and distal pin ends longitudinally separated by a pin body is provided. The proximal pin end is in direct contact with the subject surface. An ultrasonic energy source applies ultrasonic energy to the Z-pin to ultrasonically heat the Z-pin and thus locally melt the workpiece material of the subject surface and/or the workpiece body to create a melted workpiece material. The proximal pin end and at least a portion of the pin body of the Z-pin are penetrated into the melted workpiece material to create an inserted Z-pin length. The inserted Z-pin length is maintained in the workpiece body volume by solidified melted workpiece material around the inserted Z-pin length to reinforce the workpiece. A method of reinforcing a workpiece is also provided.

A method for molding a polymer composition comprises the steps of (a) providing an apparatus comprising a die and a mold cavity, (b) providing a polymer composition, (c) heating the polymer composition to a temperature sufficient to melt the polymer composition, (d) extruding the molten polymer composition through the die to form a parison, (e) capturing the parison in the mold cavity, (f) blowing a pressurized fluid into the parison, (g) allowing the molded article to cool, and (h) removing the molded article from the mold cavity.

The present invention is a method for seaming a polymeric material. The method involves forming an interface between a plurality of separate polymeric sheets of materials. Next, heat and pressure are applied to facilitate the diffusion of the polymer molecules at the interface. A diffusion weld is made when the polymer molecules diffuse across the interface.