摘要:
The green strength of compositions containing elastomers and/or up to 100 percent of reclaimed rubber is improved by the addition of crystalline or semi-crystalline butene polymers selected from the group consisting of polybutene and interpolymers made from 1-butene with at least one monomer selected from the group consisting of alpha-olefins, non-conjugated dienes, and non-conjugated polyenes. Although reclaimed rubbers are utilized, an unexpected increase in green strength of an unvulcanized blend is obtained. The reclaimed rubbers utilized in the blend may be those which have been devulcanized by mechanical energy, heat, and/or chemical agents. Additionally and preferably, the rubbers may be reclaimed through the use of microwave energy.Additionally, the unvulcanized properties of compositions containing 100 percent of scrap rubber which has been reclaimed using microwave energy are significantly improved by adding crystalline or semi-crystalline alpha-olefin polymers, such as polyethylene or polypropylene. Unexpected improvements in solvent resistance and molding properties of the uncured blends are also achieved.
摘要:
A coating for hulls of ships to be applied underwater to areas of the hull not accessible when ship is in dry dock. The means for applying the coating may take several forms: (1) a multilayered tape system having impregnated in or carrying an antifoulant and having an adhesive tape operable underwater on one side; (2) a sponge like layer having an antifoulant paint or coating liquid which can be squeezed onto the hull; (3) the use of a water soluble sponge having mixed therein microspheres of resin and pigment and microspheres of activator material such that when the microspheres or crushed, the pigmented resin, which may contain an antifoulant, and the activator are mixed and cured to form a coating on the hull while the sponge material will dissolve away when exposed over its surface to seawater. The preferred means and method for applying the coating is to mount the tape system on the dock blocks in a dry dock before the dry dock is flooded to admit the ship and is activated by the settling of the ship onto the blocks as the water is withdrawn from the dry dock. The coating may be applied by hand to small areas of damaged coating of the ship hull.
摘要:
Large quantities of reclaimed tire rubber can be incorporated into plastics material without seriously impairing its impact strength by a method which comprises the steps of swelling the reclaimed tire rubber with a quantity of monomer which is insufficient to saturate the reclaimed tire rubber and polymerizing the swollen mass.The method is effective despite the multiplicity of additives such as extenders, antioxidants and lubricants present in the reclaimed tire rubber.The preferred monomer is styrene.In certain cases the plastics material can be electroplated after suitable chemical treatment.
摘要:
A method and apparatus for continuously extruding, biaxially orienting and forming molded products from a web of thermoplastic material and further, continuously separating the products from the web selvage, stacking and handling the products and recycling the web selvage for further extrusion. The method and apparatus use continuous molding devices, namely, multiple mold cavities in a rotating polygon configuration over the peripheral surface of which the biaxially oriented web is securely and continuously positioned by a follower roller interfacing the polygon with a biaxial orientation device. Continuous and immediate interfacing is effected to prevent loss of orientation in the web which is kept at a temperature suitable for ingestion thereof into the mold cavities by vacuum, pressure or plug assist. In one preferred embodiment the inertia at the interface between the undulating peripheral surface of the rotating mold polygon and the biaxial orientation apparatus is reduced to an optimal minimum.
摘要:
A devulcanized rubber composition is disclosed which is obtained by low temperature phase transfer catalyzed devulcanization of commercial scrap rubber, such as a vulcanized polyisoprene rubber, butadiene-styrene rubber, cis-polybutadiene rubber used for vehicle tires. The devulcanized rubber of this invention is distinguishable from conventional reclaim rubber in that devulcanized rubber is substantially free of polysulfide crosslinks which are selectively broken during the process of this invention with negligible main chain scission.A process for devulcanization of scrap rubber is disclosed comprising (a) comminuting the scrap to obtain vulcanizate particles in the size range from about 325 U.S. Standard mesh (44 microns) to about 6 mesh (3.36 mm), (b) swelling the vulcanizate particles with an organic solvent having dissolved therein a predetermined concentration of an onium salt, and (c) contacting the vulcanizate particles, at a temperature below about 150.degree. C., with an aqueous solution containing OH.sup.- ions to selectively disrupt enough polysulfide crosslinks to produce a devulcanized, recyclable rubber.
摘要:
PRIMER PAINT OVERSPRAY SLUDGE IS WASHED, DRIED AND ITS THERMOSETTING RESIN BINDER FULLY CURED. THE DRY SOLIDS ARE GROUND TO FORM FILLER PARTICLES OF 200 MESH OR SMALLER. THEY ARE THEN MIXED WITH A VISCOUS LIQUID THERMOSETTING GRINDING RESIN AND FURTHER COMMINUTED UNTIL AT LEAST 90% OF THE PARTICLES HAVE BEEN REDUCED TO ONE TO FIVE MICRONS. THIS GRINDING RESIN-ULTRAFINE FILLER PARTICLE MIXTURE IS MIXED WITH ADDITIONAL THERMOSETTING BINDER RESIN AND SOLVENT TO OBTAIN A SUITABLE SPRAYABLE PRIMER PAINT.
摘要:
A method and apparatus for remelting plastic sprue material remaining adjacent a mold in an injection molding machine after an injection molding cycle of operation. Pressure is applied in a conventional manner to heated plastic for passage through a heated nozzle member in an injection molding machine. The nozzle contains a shuttle member which is moved to an injection position as the melted heated plastic is passed through the nozzle and the shuttle member, through a sprue line and then to the mold cavity. After the plastic solidifies in the mold cavity, a sprue removal pin is passed through the sprue line so as to remove the waste material or sprue material from the sprue line. This movement of the sprue removal pin moves the sprue back towards the nozzle and the sprue moves the shuttle member to a retraction position. The sprue then passes through a second path of travel which is past the heated portion of the nozzle for reheating and remelting the sprue material for later use thereof in an injection molding cycle.
摘要:
METHOD OF UTILIZING "WASTE" CELLULOSE TRIACRETATE-SECONDARY CELLULOSE ACETATE MULTICOMPONENT FILAMENTARY MATERIAL IN PRODUCING A MULTICOMPONENT FILAMENTARY MATERIAL. INVOLVES INJECTING INTO DOPE STREAM OF SECONDARY CELLULOSE ACETATE A SOLUTION OF "WASTE" MULTICOMPONENT FILAMENTARY MATERIAL OF CELLULOSE TRIACETATE AND SECONDARY CELLULOSE ACETATE, CONTRACTING THE SO-MODIFIED CELLULOSE ACETATE DOPE STREAM WITH A DOPE STREAM OF CELLULOSE TRIACETATE TO FORM A COMPOSITE STREAM, PASSING THE COMPOSITE DOPE STREAM BY LAMINAR FLOW TO A JET, AND EXTRUDING THE COMPOSITE DOPE STREAM THROUIGH THE JET TO FORM MULTICOMPONENT FILAMENTARY MATERIAL. THEREAFTER MAY SELECTIVELY SAPONIFY SO AS TO REGENERATE CELLULOSE FROM THE CELLULOSE ACETATE, RESULTING IN MULTICOMPONENT FILAMENTS OF CELLULOSE TRIACETATE AND REGENERATED CELLULOSE.
摘要:
A process for continuously monitoring and controlling product film quality from a polymer production unit and for automatically separating acceptable and unacceptable polymer product includes the steps of continuously formulating a solid particulate polymer product in the polymer production unit; withdrawing a product sample and preparing a film from the product sample; analyzing the film properties; continuously delivering the product remaining after product sampling to a residence holding device; and providing a signal representative of the film analysis so as to divert acceptable product in the holding device to product storage or unacceptable product to a by-product delivery line.
摘要:
The instant invention is directed to a process for dissociating cellular and non-cellular polyurethane resins into re-usable starting products for the isocyanate polyaddition process, wherein the polyurethane is reacted with associates of lactams and adduct-formers having at least two Zerewitinoff-active hydrogen atoms at from 150.degree. to 250.degree. C., optionally at elevated pressure, the improvement wherein from 35 to 1000 parts, by weight, based on 100 parts, by weight, of the polyurethane, of an associate mixture of:(a) from 4 to 50 parts, by weight, of a lactam or azalactam, based on 100 parts, by weight, of polyurethane; and a mixture of:(b) water and/or a compound having a molecular weight of from 62 to 200 having at least two Zerewitinoff-active hydrogen atoms; and(c) a polyhydroxyl compound having a molecular weight of from 300 to 6000; is used, and the proportion by weight of components (b) to (c) is from 1:10 to 10:1, and wherein said component (a) is used in a quantity such that said 35 to 1000 parts comprises from 4 to 50 parts of component (a).