Multifunctional additive

There always has been an interest in additives that perform both a plasticising and heat stabilising effect. The most obvious of these is epoxidised soya bean oil (ESBO), or epoxidised esters, which can be incorporated at 2-6 phr (particularly with mixed metal heat stabilisers), to improve heat stability by HC1 absorption and also give a secondary plasticisation 

Other products proposed to give a combination of heat stabilisation and plasticisation are plasticiser thiols (44) and chlorinated paraffin types (168, 209). 

The heat stabilising action of polymeric plasticisers has also been investigated (181, 223). 

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Anorin-38 has also shown an interesting effect as a multifunctional additive (a single additive to replace many of the conventional additives) for natural rubber (NR). It showed excellent blending behavior and compatibility with NR. Aorin-38 enhances the tensile properties and percent elongation, decreases fatigue, acts as an antioxidant and antiozonant, and positively affects many of the other properties, apart from acting as a process aid and a cure enhancer [183-186]. 

For use in lubrication oils Ca salts of isostearyl ether carboxylic acids are described as multifunctional additives to achieve a good water tolerance of the oil and good antiwear characteristics [182]. 

Development of eco-friendly processing aids/multifunctional additives (MFAs)... 

A-l,3-dimethylbutyl-A -phenyl quinone diimine (6QD1) has been introduced as a multifunctional additive for diene rubbers and provides an advantage in mixing characteristics (functions as peptizer and improves scorch safety) as well as improved performance (better antioxidant activity than paraphenylenediamine antidegradants) of the end products [36]. 

S. Guhathakurta, S. Anandhan, N.K. Singha, R.N. Chattopadhyay, and A.K. Bhowmick, Waste natural gum as a multifunctional additive in mbber. Journal of Applied Polymer Science, 102, 4S97-4907, 2006. Downloaded from http /www.azom.com/details.asp newsID = 1133. Site accessed on December 6, 2006. Downloaded from bttp //www.toyobo.co.jp/e/seibin/car/torikumi/torikumi.btml. Site accessed on Febmary 26, 2006. 

S. Bin Ibrahim, R. Huizenga, D. Oakley, and K. Sithamparam. Multifunctional additive to cement slurries. Patent WO 0166487, 2001. 

These compounds are multifunctional additives. They can act as heat stabilisers, radical traps, decompose hydroperoxides, UV absorbers, etc. (iv) UV absorbers. This is the largest class of UV stabilisers. They work on the same principle as sun-screen lotions they contain chromophores that can absorb light in the 280-400 nm region and release the excess energy as heat and not high-energy radiation. They must be stable under processing conditions and should not react with the polymer nor decompose with UV radiation. 

With respect to the Agency, Section 5 of TSCA has made EPA more familiar with trends in the metalworking fluids industry, the chemical components of the fluids, and the interactions between the various components. Major trends in the industry are (1) a shift from the traditional oil-based to the rapidly growing water-based fluids (2) a shift from the use of the nitrosating agent nitrite as a rust inhibitor (3) the use of multifunctional additives and (4) the careful monitoring of various factors and additives associated with these fluids. 

A multifunctional additive of carbonate-detergents RMs retarded the decomposition of ZDDP in the ISOT test (Yamada et al., 1992). Mixtures of ZDDP plus carbonate-detergents RMs additive have been reported to have synergistic effects on detergency, see Chapter 3.3 on tribochemical interactions of hard-core RMs and ZDDP (Inoue, 1993 Ramakumar et al., 1994 Willermet, 1995a and 1995b Yin et al., 1997)... 

II) Zinc dialkyldithiophosphates as multifunctional additives in lubrication formulations... 

Table 3.11. The chemistry of tribofilm generated by multifunctional additives composed of soft-core and hard-core reverse micelles (RMs) in oil formulation. Evaluation of tribofilm by XANES spectroscopy (Varlot et al., 2001)...

Micellar copper particles (and copper oxide) can give maximum benefit when used as multifunctional additives in liquid lubricants or greases, internal-combustion (IC) engines, fuels, cutting fluids, and hydraulic fluids. 

Thin-layer chromatography (TLC) has been used for estimating the remaining useful life of engine oil including depletion of the multifunctional additive ZDDP. It was found that the soot from the oil did not interfere with the spot intensity since these particles did not travel with the mobile phase. The TLC technique has the potential to be a good supporting technique for estimation of chemical additives depletion (Brook et al., 1975 Coates, 1971). This technique is comparatively easy, very cheap, does not need sophisticated and expensive instruments and takes less than an hour. 

Recently they have acquired practical importance as so-called multifunctional additives for improving performance characteristics of lubricant oils used in intensive operation engines. 

Shen, K.K. 1985. Firebrake ZB (Zinc Borate)—The unique multifunctional additive. Plastics Compounding, Edgell Communication, Cleveland, September/October. 

Barium metaborate is a truly multifunctional additive which inhibits corrosion, increases UV stability, inhibits mold growth, and has flame retarding properties when used in combination with halogenated materials. The commercial product of Buckman Laboratories is a modified product which contains 90% of active ingredient. 

Figure 7.26. Effect of multifunctional additive on bound rubber. [Adapted, by permission, from Ismail H, Freakley P K, Sheng E, Eur. Polym. J., 31, No. 11, 1995, 1049-56.]...

The quantities of multifunctional additives used must be selected with care as each type and grade of carbon black requires a specific but different amount to achieve optimum performance. To achieve optimum adhesion, the concentration of additive should coat the surface of carbon black with a monomolecular layer. Building additional layers on the carbon black surface reduces adhesion which also reduces tear strength. 

Diamine salts of fatty acids are used as multifunctional additives in natural rubber compounds filled with carbon black.They affect the elastomer-carbon black interface. With an increased concentration of multifunctional additive, the concentration of bound rubber decreases but dispersion of carbon black is improved. In silica filled rubber, multifunctional additive also improves the dispersion of silica, but in addition, it decreases the negative influence of silica filler on vulcanization rate. 

This chapter, in the view of some readers, may contain information too general to be useful. At the same time, it is very important to stress that the development of high technology products requires adequate effort from the formulators. Fillers produced today are no longer just low cost filling materials but are sophisticated multifunctional additives. They can contribute to a decreased total cost of final products but only if the functions which they were designed for are fully utilized in the product design. This requires sufficient effort and data to produce results. REFERENCES... 

The simplest concept of a multicomponent additive is a straightforward mixture of individual additives each of which contains a single key active element, and in fact many multicomponent additives are just that. But since it is logically possible to have more than one type of key functional group in the same molecule, this is another kind of multicomponent additive to consider. There is a fundamental difference between a multifunctional additive compound of this kind and the additive structure with more than one key element but only a single functional group, such as is found in the zinc dialkyl dithiophosphates Zn[SP(S) (OR>2]2 dithiophosphate esters of the type RS-P(S) (OR)2 ... 

Cetane improvers based on fatty compounds have been reported. The use of nitrate esters of fatty acids in diesel fuel was reported in a patent (Poirier et al., 1995). Multifunctional additives consisting of nitrated fatty esters for improving combustion and lubricity have been reported (Suppes et al., 2001 Suppes and Dasari, 2003). Glycol nitrates of acids of chain lengths C, C, C,, Cj and Gj (oleic acid) were also prepared and tested as cetane improvers with glycol nitrates showing better... 

Ghosh et al. (32) had developed a new vulcanization technique to mitigate the cure-rate mismatch of NR/EPDM blends by introducing a multifunctional additive, namely, DIPDIS. In order to control the curative diffusion from the nonpolar to polar elastomer, EPDM has made more polar through its reaction with DIPDIS. Although EPDM used in the investigation has a low unsaturation content (5%), it will react with DIPDIS and yield rubber-bound intermediates as shown in Fig. 15.2 (32). It was... 

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