Sizing agents natural

Fillers e.g. calcium carbonate, kaolin, titanium dioxide Sizing agents, starches Natural dyes, brighteners Retention aids... 

Diketene also is widely employed as a natural and synthetic fiber cross-linking agent, wood preservative and paper-sizing agent. Both it and /3-propiolactone have wide application as chemical intermediates. The synthetic applications of diketene for the synthesis of aromatic, heterocyclic and aliphatic compounds is exceptionally extensive (74ACR265). 

An alternative approach to understanding the role which silane-based fiber sizes play in fiber-matrix adhesion has been proposed in which the three-dimensional nature of the interphase formed by the interaction of the sizing agent with the bulk matrix has been shown to be a potential key factor in understanding the role that fiber sizings have in affecting fiber-matrix adhesion and composite mechanical properties. 

The service performance of rubber products can be improved by the addition of fine particle size carbon blacks or silicas. The most important effects are improvements in wear resistance of tire treads and in sidewall resistance to tearing and fatigue cracking. This reinforcement varies with the particle size, surface nature, state of agglomeration and amount of the reinforcing agent and the nature of the elastomer. Carbon blacks normally are effective only with hydrocarbon rubbers. It seems likely that the reinforcement phenomenon relies on the physical adsorption of polymer chains on the solid surface and the ability of the elastomer molecules to slip over the filler surface without actual desorption or creation of voids. 

Silanes exhibit hydrophilic and hydrophobic properties. The molecule has both a non-polar and a polar component. The non-polar organic alkyl group is the vehicle for the water-repellent action. The effectiveness, durability and stability of the waterproofing agent depends on the size and nature of this group (Huls, 1991). 

Blends of natural silk and polyester fibres (35 65) are sometimes used for dress goods, blouse fabrics and men s fashion wear. Sizing agents and soils are removed by washing with a minimum tension in open soaper containing 1 g/1 non-ionic detergent and 1 ml/1 NH3(25%) at 50 C. 

To achieve good absorbancy of cotton, dirt, sizes and natural impurities are usually removed by alkaline scouring. If these impurities are not removed, can lead to the formation of AOX in the effluent when NaOCl is used as a bleaching agent [45]. 

Deposits are a natural result of problems at the wet-end of a paper or board machine. They are normally related to problems of retention of the sizing agent although they can be caused by incompatibility. They may occur in the stock approach system, on the wire, on the presses or in the drying section. Many of the reasons for deposits have already been covered, but this section will try to summarise them. 

Rischel, A-G. (1992). Natural plant sizing agents in Oriental papers and the importance of resizing such papers after washing. In S. Fairbrass (Ed.), Confererute, Manchester, 1992 Papers (pp. 222-227). Institute of Paper Conservation. 

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