Carboxyl terminated butadiene acrylonitrile rubber

CTBN Carboxyl-Terminated Butadiene Acrylonitrile Rubber... 

CTBN carboxyl-terminated butadiene-acrylonitrile rubber DETA diethylenetriamine... 

The carboxyl terminated butadiene-acrylonitrile rubber, which is soluble initially in the liquid phase, precipitates out as a second phase during the crosslinking reaction of the epoxy. The cured specimens are... 

CTBN Carboxyl terminated butadiene acrylonitrile rubber... 

Fig. 13. Experimental CPC (A) and calculated binodal (broken curve) and spinodal (dotted curve) curves for a binary system composed of a DGEBA-based epoxy monomer (M = 479 gmol ) and a carboxyl-terminated butadiene-acrylonitrile rubber (CTBN) (Reprinted from Polymer, 30, D. Verchere, H. Sautereau, J.P. Pascault, S.M. Mos-chiar, C.C. Riccardi, R.J.J. Williams, Miscibility of epoxy monomers with carboxyl-terminated butadiene-acrylonitrile random copolymers, 107 -115, Copyright (1989), with kind permission from Butterworth-Heinemann journals, Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington 0X5 1GB, UK)...

Rubber was a carboxyl-terminated butadiene-acrylonitrile copolymer. Mean diameter of rubber particles =1.6 pm. Rubber concentration was 15 phr, giving volume fraction of 0.18 4 Containing vf (glass) = 0.1 rubber = 15 phr... 

Fig. 13. TXT cure diagram temperature of cure vs. the times to phase separation (doud point), gelation and vitrification for a neat and two rubber-modified systems. of the neat system is also included. The systems studied were DER331/TMAB O, gelation , vitrificaticm modified with IS parts rubber per hundred parts epoxy 1) pr eacted carboxyl-terminated butadiene-acrylonitrile (CTBN) copolymer containing 17% acrylonitrile (K-293, Spencer Kellog Co.) A, phase separation , gelation , vitrification, and 2) polytetramethylene oxide terminated with anmiatic amine (ODA2000, Polaroid Corp.) A. phase separation O, gelation O, vitrification. (DER331/TMAB/ K-293 data from Ref. )...

Additives. Acrylonitrile-butadiene rubbers were provided by BFGood-rich (Brecksville, OH). The amino-terminated butadiene-acrylonitrile (ATBN) rubber was obtained by reacting carboxyl-terminated butadiene-acrylonitrile (CTBN) with an excess diamine, Unilink 4200 (from UOP, El Dorado Hills, CA) consequently, free diamine molecules always remained in the rubber. The rubbers have almost the same molar mass but different end groups, which have been characterized in a previous work (20). Their structures are given in Chart I, and they are described in Table I. The two poly(ether sulfone)s (PESs) (Victrex, from ICI, United Kingdom) used in this study are described in Table II. 

The rubber-toughening process has been one of the most successful methods for modifying polymer toughness. The incorporation of small amounts of rubber into polymer matrices has resulted in significantly improved fracture resistance (1). Particularly interesting improvements in the toughness of epoxies have been accomplished by the addition of carboxyl-terminated butadiene/acrylonitrile (CTBN) elastomers (2,3). 

Epoxy prepolymers with rubber CORI Carboxyl-terminated butadiene-acrylonitrile random copolymer Taha et al. 1997... 

The second ABCP-type materials of commerce are the rubber-toughened epoxy resinsUsually the epoxy resins are based on the diglycidyl ether of bisphenol A (DGEBA). Carboxyl-terminated butadiene-acrylonitrile (CTBN) rubber is the elastomer of preference. A typical composition is ... 

Several methods have been investigated to improve the fracture toughness of BMI resins, the most used technique being the incorporation of a second phase formed by the dispersion of rubber particles into the cross-linked matrix. Carboxyl-terminated butadiene-acrylonitrile elastomers (CTBN), which are very effective with epoxy resins, are also frequently added to BMI adhesives. The general formula of CTBN rubbers is ... 

Toughening epoxy matrices using liquid reactive rubbers (such as carboxyl-terminated butadiene acrylonitrile, CTBN, or the amine-terminated equivalent, ATBN) has been widely reported in the literature. Spherical rubber particles of a proper size distribution (usually 1-5 pm) can effectively enhance the toughness through crack blunting or cavitation mechanisms. However, rubber modification of epoxies becomes... 

In order to improve the internal stress performance even further or to provide toughness for potting and adhesive applications it is advantageous to introduce reactive additives to the basic epoxide compound formulation. One of the most popular additives that has found considerable use in this type of application is a rubber-like liquid copolymer known as carboxyl terminated butadiene/acrylonitrile (CTBN). The generalised molecular structure of this material is ... 

More recently Crosbie and Philips [85,86] investigated the toughening effect of several reactive liquid rubbers (carboxyl terminated butadiene-acrylonitrile, vinyl terminated butadiene-acrylonitrile, hydroxyl terminated polyether, polyepichlorohydrin) and an unspecified experimental reactive liquid rubber developed by Scott Bader Ltd. on two different polyester resins a flexibilized isophthalic-neopentyl glycol polyester resin, PVC compatible and an epoxy modified polyester resin, which is preaccelerated. The results of these studies are summarized as follows ... 

High molar mass epoxy prepolymers containing rabber dispersions based on carboxyl-terminated butadiene-acrylonitrile copolymer were prepared from initially miscible solution of low molar mass epoxy prepolymers, bisphenol A and carboxyl-terminated NBR. During chain extension inside a twin screw extruder due to epoxy-phenoxy and epoxy-carboxy reactions, a phase separation process occurs. Epoxy-phenoxy and epoxy-carboxy reactions were catalysed by triphenylphosphine. The effect of reaction parameters (temperature, catalyst, reactant stoichiometry) on the reactive extrasion process were analysed. The structure of the prepolymers showed low branching reactions (2-5%). Low molar mass prepolymers had a Newtonian rheological behaviour. Cloud-point temperatures of different reactive liquid butadiene aciylonitrile random copolymer/epoxy resin blends were measured for different rubber concentrations. Rubber... 

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