Acrylic acid volatile

The initiator was injected into the second barrel where it mixed with the unmelted polypropylene in the solids conveying zone. In the melting section, a process temperature of about 200°C resulted in an initiator half-life on the order of 5 sec. This is about the residence time in the melting section, so that when the acrylic acid was injected into barrel 4, polypropylene radicals would already have been formed. The grafting reaction of acrylic acid was essentially completed within one barrel section. An atmospheric vent was used in the fifth barrel to remove unreacted acrylic acid volatiles and entrapped air. 

Esters of allyl alcohol, e.g., diallyl phthalate, are used as bifunctional polymerization monomers and can be prepared by simple esterification of phthalic anhydride with allyl alcohol. Several acrylic esters, such as ethyl or methyl acrylates, are also widely used and can be made from acrylic acid and the appropriate alcohol. The esters are more volatile than the corresponding acids. 

A mixture of 1 kg. (18.9 moles) of acrylonitrile Caution—volatile toxic material), 6 g. of hydroquinone, 14 g. of copper powder, 648 g. of ice, and 1012 ml. of concentrated sulfuric acid is heated gradually under a reflux condenser on a steam bath. The exothermic reaction is controlled by cautious application of heat, particularly during the first hour. Heating is continued for 48 hours, after which the mixture is cooled and the precipitated ammonium bisulfate is filtered off. The crude acid is distilled by dropping it into a distilling flask loosely packed with fine copper wire and heated to a bath temperature of 250°. The system is maintained under a pressure of about 10 mm, and the distillation receiver is packed in ice. Approximately 1 kg. of clear, colorless distillate is obtained which is shown by analysis to be 86% acrylic acid free of sulfur and nitrogen. 

The remaining organic phase consists of acetic and acrylic acids, and less volatile conqwnents. Following the heuristic to remove largest quantities first, the second column, C-2, should separate into two streams, predominantly acetic and acrylic acids. 

Organosulphides produced by marine microorganisms make a particularly significant contribution to the atmospheric sulphur burden. The most characteristic compound is dimethyl sulphide (DMS (CH3)2S Fig. 3.4a). This volatile compound is produced by marine phytoplankton, such as Phaeocystis pouchetii, in the upper layers of the ocean by the hydrolysis of beta-dimethylsulphoniopropionate (DMSP (CH3)2S+CH2CH2COO ) to DMS and acrylic acid (CH2CHCOOH) ... 

Acryloyl chloride can be obtained commercially, but care must be taken when storing the material, and in any case it should not be stored for long periods (since an exothermic polymerization may occur) acryloyl chloride can be readily prepared by heating acrylic acid with excess benzoyl chloride and distillation of the volatile component. 

Some of the volatile odorous components of algae, such as dimethyl sulfide, are unpleasant and are mainly distributed in Chlorophyta and also in some Rhodophyta [112]. Dimethyl sulfide and acrylic acid have resulted from the enzymatic cleavage products of dimethyl-jS-propiothetin (dimethyl-2-carboxyethylsulfonium hydroxide), from Enteromorpha intestinalis and Acrosiphonia centralis [113], which is a metabolite of methionine [45] released into the sea water [112]. 

Intermediate in production of plastics as comonomer with vinyl chloride, acrylonitrile, acrylates etc. Reacts with alcohols and halides to give carboxylic acids. Volatile liq. d o 1.218. Fp -122.5°. Bp 31.7°, Bp °(37°). ... 

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