Continuous impregnation process

Fibres can also be prepared in the form of a mat consisting of randomly oriented short fibres held loosely together hy a chemical hinder, sometimes in a carrier fabric, as a continuous thin flat sheet. Mats are commercially available as blankets of various weights, thickness, and widths, which can he cut and shaped for use as preforms in some closed-mould processes and in hand lay-up, press moulding, bag moulding, autoclave moulding, and in various continuous impregnating processes. 

Thermosol dyeing. The characteristics of low-molecular-weight polyester dyes can be utilized in thermosol dyeing processes. In this continuous dyeing process the material is impregnated with the dispersed dye, dried, and heated to a temperature of approximately 200-210°C. The dyestuff is fixed by sublimation into the fiber. 

Ion-exchange resin methods, which are well known as useful preconcentration methods for trace ions, have some drawbacks slow adsorption and desorption rates, poor selectivity, and requirement for a concentrated solution of electrolyte such as acid, base, or neutral salts for recovery. Chromatographic methods in which solvent extraction procedures have been used in a continuous separation process using inert supports impregnated with the extractants combine many of the advantages of both liquid-liquid extraction and ion-exchange chromatography, which are the two of most im-... 

Without use of accelerators, external heat is required, making a system suitable for mechanical processes, such as hot press molding and continuous impregnation of sheet and profile. Temperatures in the range 120-160C (248-320F) are used to cure in a short cycle accelerators offer no advantage as the rate of cure depends on thermal decomposition of the peroxide, and typical cycle times are 1-10 min. 

The teehnique used for slurry infiltration is the same as that used for glass (Section 15.3.2.2) and to improve the densification, it is normal to adopt a multiple slurry impregnation process. The technique is most effective for glass ceramics, although recent attention has concentrated on SiC reinforcement. A limitation when coating continuous fiber is that the impregnated and dried tow has an excess of matrix particles, which persists after densification. 

CIC (continuously impregnated compound) The batch production process is replaced with a continuous process, for larger volumes with more consistent properties... 

The ratios obtained by the two methods [S] allow elucidating the role of the carbon surface oxidation and the kind of the media (aqueous or m hanol) with req)ect to the impregnation process, i.e. to the incorporation of Cu into the intonal pore network or onto the external support surface. In our case (Table 5) there is a continuous increase of the concentration of Cu in the internal surface, which for the different samples varies between 3.1 and 9.4. The ACM... 

Dyeing is carried out either as a batch exhaustion process, or as a continuous impregnation and fixation process. In exhaust dyeing, all the material is in contact with all the dye liquor from which the fibres absorb the dyes. The dye... 

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