Liquid curing method

This system involves the use of some form of heating by air or steam in a chamber in a manner such that the vulcanization occurs immediately after the rubber is formed in an extruder or calender. This is a suitable process for extruded profiles and calendered sheets and conveyor belts. Liquid curing method (LCM) is also a continuous process which involves the use of suitable hot liquid baths in which extruded profiles can be passed through and vulcanized continuously. Items can be cured rapidly at temperatures from 200°C to 300°C however the compounds must be suitably designed to prevent porosity as this is a common problem with any extrudate. Suitable materials for curing medium includes bismuth-tin alloys, an eutectic mixture of potassium nitrate and... 

Mi, F. L., Shyu, S. S., Lee, S. T., and Wong, T. B. (1999a). Kinetic study of chitosan-tripolyphos-phate complex reaction and acid-resistive properties of the chitosan-tripolyphosphate gel beads prepared by in-liquid curing method. J. Polym. Set B Polym. Phys. 37(14), 1551-1564. 

Any method of vulcanising rubber products which proceeds without interruption from start to finish as compared to the method of vulcanising separate batches of products or sections of a product. Continuous vulcanisation processes include the cold curing of proofed cloth, the vulcanisation of belting and flooring, of cables and certain extruded products by either the Liquid Curing Medium, Fluid Bed, Microwave, or Hot Air techniques. 

The pigments are incorporated into the resins before crosslinking to ensure homogeneous coloration. This can be done in the molten resin, for example in a kneader at about 90°C, or in dissolved or liquid resins by the liquid resin method. Ball mills are normally used for coloring prewetted powder molding compounds that have not yet been cured. 

There are numerous methods of applying liquid systems to different surfaces, and the following sections will discuss some of them. Many of these techniques are used in both UV and EB curing processes. Some are very specific to UV technology, and these will be dealt with separately in connection with that curing method. 

Vulcanization by the traditional curing methods utilized in the rubber industry is based on sulfur or sulphur-containing compounds and is also the most widely applied technique for curing liquid rubbers containing macromolecules with double bonds. Chinons, peroxides, phenol formaldehyde resins, and other compounds are often used for curing liquid rubbers as an alternative sulfur vulcanization. 

Liquid Cure Medium (LCM) uses a eutectic mixture of salts to heat the extrudate. The molten salt bath usually has a metal conveyor to keep the rubber eompound submersed. This method has good heat transfer to the rubber. However, cleaning salt off the extrudate can be difficult and satisfactory disposal of dilute salt rinse is beeoming increasingly difficult. This method is advantageous for articles with the low compression set obtained by using peroxides. Sulfur can be used as a coagent to minimize surface tack. Deformation problems versus other atmospheric methods are sometimes minimized. 

Type of adhesive Common forms available Solid Film Paste Liquid Solvent solution, emulsion Cure method Solvent release Chemical reaction Processing conditions Room High temperature temperature Pressure required Pressure not required... 

Liquid curing medium (LCM) is a practical method provided that a rapid cure rate system and a high viscosity CSM are selected. A peroxide system may leave a tacky surface unless complete submersion or rain of the LCM on the part is provided. 

This is a method for making hollow articles using liquid plastics, particularly PVC plastisols. A shell-like mould is heated to a pre-determined temperature (typically 130°C for plastisols) and the liquid is then poured into the mould to completely fill it. A period of time is allowed to elapse until the required thickness of plastic gels. The excess liquid is then poured out and the plastic skin remaining in the mould is cured in an oven. The moulding is then taken from the mould. 

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