Page 215 - Handbook of Adhesion Promoters

208 Selection of Adhesion Promoters for Different

9.26 TIRES

Numerous additives are used in the tire production to increase adhesion between tire struc-
tural elements. They include Cofill 11 GR; Cohedur A 200, H 30, and RDL; Dow Corning
Z-6518, Z-6920, Z-6925, Z-6940, and Z-6945; NXT & NXT LowV; and Silquest A-1589
& A-1891. The main active components of formulations of these adhesion promoters are
hexamethoxymethylmelamine ether, resorcinol, and mercapto- and vinyl-silanes.
Adhesion of natural rubber to brass plated steel cords was improved using tri-com-
ponent system consisting of resorcinol (Cohedur SR), formaldehyde resin and silica. 1
Also, cobalt boron acrylate and kaolin modified rubber were used as alternative adhesion
1
promoters. The kaolin modified rubber enhanced the static and dynamic adhesion and
1
bond durability as compared to a widely used adhesion promoters in the tire industry.
A rubber-to-particle adhesion promoter is a mixture of resorcinol-formaldehyde
2
resin prepolymer and latex (resorcinol-formaldehyde latex). It is distributed on surfaces
of the particles so as to cause chemical bonding between the surfaces of the particles and
rubber of the tread part to improve the scratching effect and develop a mechanism for
improving friction on ice (the particles are protruded from surface of the tread at a time the
particles are contacted with road face so as to destroy thin-wall portions of ice covering
2
the road face, which is derived from compressed snow).
3
The weft inserted warp knit fabric tape includes an adhesion promoter. Typical
examples of adhesion promoters included resorcinol formaldehyde latex, isocyanate-
based material, epoxy-based material, and materials based on melamine formaldehyde
3
3
resin. The adhesion promoter may be applied to the yarns before forming into a fabric.
The rubber composition contained a cobalt salt of an organic acid as an adhesion pro-
4
moter in the amount of 0.1-0.2 phr. It acts as an adhesion promoter of steel cord adhe-
4
sive.
The resorcinol-blocked isocyanate compositions are formed in reaction of resorcinol
5
compound and two or more isocyanate compounds. They have two or more unblocking
temperatures and/or melting characteristics that provide some unique properties (e.g.,
improved adhesion of rubber reinforcing materials to rubber materials or compounds). 5
The resorcinol-blocked isocyanate compositions are applied by fabric dipping. A cobalt
5
salt can still be added to the composition.
The non-pneumatic tires require adhesive systems for bonding cured polyurethane to
6
uncured (unvulcanized) diene elastomers. In this formulation, N,N-diethylacetoacet-
6
amide (Promoter C) has found application as an adhesion promoter.
REFERENCES
1 Abou-Kandil, AI; Awad, A; Darwish, N; Shehata, AB; Saleh, BK, Int. J. Adh. Adh., 44, 26-35, 2013.
2 Kamada, S, US20120232186, Toyo Tire & Rubber Co., Ltd., Sep. 13, 2012.
3 Ternon, GLR; Michiels, DF, US7614436, Milliken & Company, Nov. 10, 2009.
4 Ogura, Y; Sasaka, N; Mimasu, Y; Mishima, R; WO2013008787, Bridgestone Corporation, Jan. 17, 2013.
5 Durairaj, RB; Jesionowski, GA; Lawrence, MA, US7705088, Indspec Chemical Corporation, Apr. 27,
2010.
6 Delfino, A; Chenaux, P; Deforel, C, US20130000841, Conception Et Developement Michelin S.A.,
Jan. 3, 2013.