Nitriles, liquid

Carboxylated nitriles, hydrogenated nitrile, liquid nitriles and blends with PVC are also commercially available. 

Figure 5.28. In situ wet-ETEM of real-time catalytic hydrogenation of nitrile liquids over novel Co-Ru/Ti02 nanocatalysts, (a) Fresh catalyst with Co-Ru clusters (arrowed at C). The support is marked, e.g., at u. (b) Catalyst immersed in adiponitrile liquid and H2 gas in flowing conditions growth of hexamethylene diamine (HMD) layers (at the catalyst surface S in profile, arrowed) at 81 °C, confirmed by composition analysis and mass spectrometry, (c) ED pattern of HMD in (b) in liquid environments. Further growth is observed at 100 °C. The studies show that wet-ETEM can be used to design a catalytic process (after Gai 2002). (d) Scaled up reactivity data for novel Co-Ru/Ti02 nanocatalysts confirming wet-ETEM studies of high hydrogenation activity of the nanocatalyst (2). Plots 1 and 3 are the data for Raney-Ni complexes and Ru/alumina catalysts, respectively.

LLDPE and amine-terminated butadiene nitrile liquid rubber (ATBN) with di-peroxy initiator into the rubber tire powder. The compounded blends were molded into test specimens. The data showed about 50% better tensile and impact strength after compatibilization [Duhaime and Baker, 1991]. 

Later, in 1974, amine reactive versions of the liquid nitrile polymers (ATBN) were issued, thereby offering another way to introduce rubbery segments into a cured epoxy resin network. References are cited which provide detailed discussions of nitrile rubber, carboxylic nitrile rubber and both carboxyl- and amine-terminated nitrile liquid polymers (1-4). Table I illustrates CTBN and ATBN products structurally. Table II provides properties for typical solid carboxylic nitrile elastomers. 

Wide-ranging documentation exists which covers modification of epoxy resins using carboxyl-terminated polybutadiene/acrylo-nitrile liquid polymers in which addition esterification (alky-... 

Diener (46) and Tsuchiya (47) have shown carboxyl-reactive nitrile liquids to have utility in both aqueous and non-aqueous anodic and cathodic electrodeposition systems aimed at primers and coatings. Excellent coating adhesion is demonstrated with advantages noted in moisture resistance and reverse impacts. Diener suggests an electrocoat system as a replacement for standard solvent-based primers used with aircraft adhesives. 

Thicker epoxy-based coatings, highly flexibllized with amine-reactive nitrile liquid polymer, have been described by Mendelsohn (50) in which the flexibilizing hardener is comprised of an admixture of ATBN, fatty polyamide and boron trifluoride/amine complex. This coating ages well at 100°C and has excellent toughness/ flex with good abrasion and vibration absorption properties. 

Numata and Kinjo (52) have shown rubber-modified isocyanurate-oxazolidone resins may be effectively modified with carboxyl-reactive nitrile liquids. The viscoelastic behavior of models using a polyglycidyl ether of phenol-formaldehyde novolac resin and di-phenylmethane-4,4 -diisocyanate is discussed. Such resins have suggested utility in thin films as electrical varnishes. 

Elastomer modification of two-package epoxy coatings has been carried out either with rubber addition to the epoxy component or to the hardener component. Amine-reactive nitrile liquids have been examined extensively in polyamide cured epoxy coatings. The... 

As previously mentioned in this chapter, carboxyl-reactive nitrile liquids appear to be the preferred modifiers for latent epoxy structural film adhesives. One of the major components used in formulating these adhesives is a solid epoxy resin of similar molecular weight (1000). This limited coatings study suggests that similar elastomer-modified epoxy resins are equally impressive in solution epoxy coatings. In addition. Table XI/Recipe 3 features a high impact coating modified with both liquid and solid carboxylated nitrile elastomers. 

Carboxylic nitrile liquid and solid elastomers are used to prepare elastomer-modified epoxy liquid and solid resins when it is desirable to have the modifier in the epoxy portion of the system. This is effected through alkyl-hydroxy esterification reactions. This is covered in the literature for uncatalyzed liquid resins (9), for tert-amine catalyzed systems (10), for tert-phosphine catalyzed systems (11), for low molecular weight solid resins advanced from the liquid state (12) and for liquid and solid resins where an additional rubber vulcanization step is carried out in addition to the alkylhydroxy ester adducting step (13). Such adduct preparations offer formulation stability with a wide range of hardener types amines, anhydrides, catalytic, Lewis acids/bases. 

The amine-reactive nitrile liquids are useful in formulating a modified hardener package through admixture with an amine, amidoamine or fatty poly-amide curing agent of choice (14). And novel elastomer-modified epoxy resin hardeners giving excellent reported adhesive properties have begun to appear in the marketplace (15). 

ATBN Amine-terminated butadiene nitrile liquid rubber ATR Attenuated total reflection (in FT-IR) a-TREE Analytical temperature rising elution fractionation BAE Tetrakis[3,5-bis(trifluoromethyl)phenyl]borate BC Branch content... 

FS(0)20CH3. Colourless liquid, b.p. 94°C. Functions as a powerful methylating agent, even for amides and nitriles which are not attacked by conventional alkylating agents like dialkyl sulphates. 

The crude acetonitrile contains as impurity chiefly acetic acid, arising from the action of phosphoric acid on the acetamide. Therefore add to the nitrile about half its volume of water, and then add powdered dry potassium carbonate until the well-shaken mixture is saturated. The potassium carbonate neutralises any acetic acid present, and at the same time salts out the otherwise water-soluble nitrile as a separate upper layer. Allow to stand for 20 minutes with further occasional shaking. Now decant the mixed liquids into a separating-funnel, run off the lower carbonate layer as completely as possible, and then pour off the acetonitrile into a 25 ml, distilling-flask into which about 3-4 g. of phosphorus pentoxide have been placed immediately before. Fit a thermometer and water-condenser to the flask and distil the acetonitrile slowly, collecting the fraction of b.p. 79-82°. Yield 9 5 g. (12 ml.). 

Boil 5 ml. (5-1 g.) of benzonitrile and 75 ml. of 10% aqueous sodium hydroxide in a 200 ml. flask under a reflux water condenser until no more oily drops of unchanged nitrile run down from the condenser (usually about 40 minutes). Th detach the condenser and boil the solution in the open flask for a few minutes to remove free ammonia, Cool the liquid, and add concentrated hydrochloric acid cautiously until precipitation of benzoic acid is complete. Cool the mixture again thoroughly, filter off the benzoic acid at the pump, and wash well with cold water. Yield, 5 8 g. (almost theoretical). Confirm the identity of the benzoic acid by the tests given on p. 347. The benzoic acid obtained in this way should be pure and have m.p. 121 a portion may if desired be recrystallised from hot water. 

B). Many nitriles when treated with hydrogen peroxide in warm alkaline solution undergo hydrolysis to amides which can thus be readily obtained in high yield. Insoluble liquid nitriles can be treated directly in the aqueous suspension, but for insoluble solid nitriles the addition of a suitable organic solvent to give a complete solution may be desirable, although the completion of the hydrolysis may not then be so readily detected. 

Place together in a 50 ml. conical flask about 1 g. of the substance and 10 ml. of 10% NaOH solution (or use apparatus in Fig. 38, p. 63)-Add a few pieces of unglazed porcelain, fit a reflux water- condenser, and boil gently for about 20 minutes. Nitriles require longer heating than amides, usually about 30 minutes. The completion of the hydrolysis of an insoluble nitrile ( .g., benzonitrile) is indicated by the disappearance of oily drops in the liquid. Cool the flask, add an excess of dil. H2SO4 and cool thoroughly. 

AUphatic nitriles are usually liquids or low melting point sohds. The most important reaction of a nitrile is its hydrolysis either by an alkaU or by an acid to the corresponding ahphatic acid characterisation of the acid enables the identity of the original nitrile to be established. 

Preparation of benzyl cyanide. Place 100 g. of powdered, technical sodium cyanide (97-98 per cent. NaCN) (CAUTION) and 90 ml. of water in a 1 litre round-bottomed flask provided with a reflux condenser. Warm on a water bath until the sodium cyanide dissolves. Add, by means of a separatory funnel fitted into the top of the condenser with a grooved cork, a solution of 200 g. (181-5 ml.) of benzyl chloride (Section IV.22) in 200 g. of rectified spirit during 30-45 minutes. Heat the mixture in a water bath for 4 hours, cool, and filter off the precipitated sodium chloride with suction wash with a little alcohol. Distil off as much as possible of the alcohol on a water bath (wrap the flask in a cloth) (Fig. II, 13, 3). Cool the residual liquid, filter if necessary, and separate the layer of crude benzyl cyanide. (Sometimes it is advantageous to extract the nitrile with ether or benzene.) Dry over a little anhydrous magnesium sulphate, and distil under diminished pressure from a Claisen flask, preferably with a fractionating side arm (Figs. II, 24, 2-5). Collect the benzyl cyanide at 102-103°/10 mm. The yield is 160 g. 

Place 45 g. of benzamide (Section IV, 188) and 80 g. of phosphorus pentoxide in a 250 ml. Claisen flask (for exact experimeutal details on the handling and weighing out of phosphoric oxide, see under Acetamide, Section 111,111). Mix well. Arrange for distillation (Fig.//, 29, 1 or Fig. II, 20, 1) under reduced pressure use a water pump with an air leak in the system so that a pressure of about 100 mm. is attained. Heat the flask with a free flame until no more liquid distils the nitrile will pass over at 126-130°/100 mm. Wash the distillate with a little sodium carbonate solution, then with water, and dry over anhydrous calcium chloride or magnesium sulphate. Distil under normal pressure (Fig. II, 13, 2 or II, 13, 6) from a 50 ml. flask the benzonitrile passes over as a colourless liquid at 188-189° (compare Section IV,66). The yield is 28 g. 

Aromatic nitriles are generally liquids or low melting point solids, and usually have characteristic odours. They give no ammonia with aqueous sodium hydroxide solution in the cold, are hydrolysed by boiling aqueous alkali but more slowly than primary amides ... 

Nitriles and simple amides differ in physical properties the former are liquids or low-melting Solids, whilst the latter are generally solids. If the amide is a solid and insoluble in water, it may be readily prepared from the nitrile by dissolving in concentrated sulphuric acid and pouring the solution into water ... 

After cooling to about 40°C (note 2) the viscous brown liquid was poured into a vigorously stirred solution of 50 g of ammonium chloride in 250 ml of 4 N HCl, which was kept at 0-5°C. The flask was also rinsed with this solution. The product was extracted 5-7 times with a 1 1 mixture of diethyl ether and pentane. The combined extracts were washed with saturated NHi Cl solution and subsequently dried over magnesium sulfate. The residue remaining after removal of the solvents in a water-pump vacuum, was carefully distilled through a 30-cm Widmer column. The desired nitrile, b.p. 84°C/15 mmHg, n 1.4487, was obtained in 72% yield. The first fraction (about 5 g) consisted mainly of the 1,3-substitution product n-C,HgC(CsN)=C=CH2. 

By-Products. Almost all commercial manufacture of pyridine compounds involves the concomitant manufacture of various side products. Liquid- and vapor-phase synthesis of pyridines from ammonia and aldehydes or ketones produces pyridine or an alkylated pyridine as a primary product, as well as isomeric aLkylpyridines and higher substituted aLkylpyridines, along with their isomers. Furthermore, self-condensation of aldehydes and ketones can produce substituted ben2enes. Condensation of ammonia with the aldehydes can produce certain alkyl or unsaturated nitrile side products. Lasdy, self-condensation of the aldehydes and ketones, perhaps with reduction, can lead to alkanes and alkenes. 

Isolation of the pure a,0 -ieomer, A 250-mL Erlenmeyer flask equipped with a magnetic stirring bar is charged with the isomeric nitriles (20 g, 0.165 mol), prepared in Part A above, and carbon tetrachloride (20 mL). A solution of bromine in carbon tetrachloride (1/9, v/v, ca. 25-30 mL) is added dropwise until the color of excess bromine persists. The reaction vessel is cooled in an ice bath for 30 min, filtered by gravity and the solvent evaporated under reduced pressure. The crude oil is distilled at reduced pressure (bp 40-42 0/0,15 mm) to give a colorless liquid (11-15 g, 55-75%) which is the pure a.p-1somer (Notes 9 and 10). 

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