Propionate plastic

Uses/Sources. Synthesis of fungicides, herbicides, pharmaceuticals, flavorings, and perfumes production of propionates and cellulose propionate plastics present naturally in dairy products... 

Although Lhe first cellulose plastic (cellulose nitrate plastic-based on an inorganic ester of cellulose) was developed in 1865. the first organic cellulose ester plastic was not offered commercially until 1927. In that year, cellulose acetate plastic became available as sheets, rods, and tubes. Two years later, in 1929. it was offered in the form of granules for molding. It was the first thermoplastic sufficiently stable to be melted without excessive decomposition, and it was the first thermoplastic to be injection molded. Cellulose acetate butyrate plastic became a commercial product in 1938 and cellulose propionate plastic followed in 1945. The latter material was withdrawn after a short time because of manufacturing difficulties, but it reappeared and became firmly established in 1955. 

PROPIONATE PLASTICS. See Cellulose Ester Plastics (Organic). 

The other hydrocarbon acids arc not a industrially significant. In many potential markets the lower price of acetic acid keeps them blocked out. Formic acid is used in textile drying and leather treatment. Propionic acid is used in the production of propionates, plasticizers, and herbicides Butyric acid finds a variety of specialty uses in producing plasticizers and esters. 

Use Propionates, some of which are used as mold inhibitors in bread and fungicides in general herbicides preservative for grains and wood chips emulsifying agents solutions for electroplating nickel perfume esters artificial fruit flavors pharmaceuticals cellulose propionate plastics. 

Cellulose acetate and mixed ester (include acetate butyrate and propionate plastics)... 

Alcohol resins, polyvinyl Alkyd resins Allyl resins Butadiene copolymers, containing less than 50 percent butadione Carbohydrate plastics Casein plastics Cellulose nitrate resins Cellulose propionate (plastics) Coal tar resins Condensation plastics Coumarone-iodene resins Cresol resins Cresol-furfural resins Dicyandiamine resins Diisocyanate resins Elastomers, nonvulcanizable (plastics)... 

Uses as a mold inhibitor in bread and cheese products in fongicides and herbicides preservative for grains and wood chips in emulsifying agents in solutions for electroplating nickel, perfume esters, artificial fruit flavors, pharmaceuticals, and cellulose propionate plastics A... 

Cellulose propionate plastics produced in a similar manner to cellulose acetate. Used in the USA for port-... 

Cellulose Acetate, Propionate, and Butyrate. Cellulose acetate is prepared by hydrolyzing the triester to remove some of the acetyl groups the plastic-grade resin contains 38 to 40%... 

Some propionic acid is converted iato herbicides (qv) such as Stam (Rohm and Haas) (3, 4 -dich1oropropionanilide) and iato ceUulose acetate propionate, a plastic sheeting and mol ding precursor. 

Methylphenol is converted to 6-/ f2 -butyl-2-methylphenol [2219-82-1] by alkylation with isobutylene under aluminum catalysis. A number of phenoHc anti-oxidants used to stabilize mbber and plastics against thermal oxidative degradation are based on this compound. The condensation of 6-/ f2 -butyl-2-methylphenol with formaldehyde yields 4,4 -methylenebis(2-methyl-6-/ f2 butylphenol) [96-65-17, reaction with sulfur dichloride yields 4,4 -thiobis(2-methyl-6-/ f2 butylphenol) [96-66-2] and reaction with methyl acrylate under base catalysis yields the corresponding hydrocinnamate. Transesterification of the hydrocinnamate with triethylene glycol yields triethylene glycol-bis[3-(3-/ f2 -butyl-5-methyl-4-hydroxyphenyl)propionate] [36443-68-2] (39). 2-Methylphenol is also a component of cresyHc acids, blends of phenol, cresols, and xylenols. CresyHc acids are used as solvents in a number of coating appHcations (see Table 3). 

The cellulose esters with the largest commercial consumption are cellulose acetate, including cellulose triacetate, cellulose acetate butyrate, and cellulose acetate propionate. Cellulose acetate is used in textile fibers, plastics, film, sheeting, and lacquers. The cellulose acetate used for photographic film base is almost exclusively triacetate some triacetate is also used for textile fibers because of its crystalline and heat-setting characteristics. The critical properties of cellulose acetate as related to appHcation are given in Table 10. 

The most important of the esters is cellulose acetate. This material has been extensively used in the manufacture of films, moulding and extrusion compounds, fibres and lacquers. As with all the other cellulose polymers it has, however, become of small importance to the plastics industry compared with the polyolefins, PVC and polystyrene. In spite of their higher cost cellulose acetate-butyrate and cellulose propionate appear to have retained their smaller market because of their excellent appearance and toughness. 

If butyric or propionic acids are included in the esterifying mixture, acetate butyrates and acetate propionates are formed. These, requiring less plasticizer, are tougher and more moisture resistant material for making automobile steering wheels. 

Chromatograms can be made handleable and storable by treatment with plastic dispersions, based on polyacrylic ester, polyvinyl chloride or polyvinyl propionate, such as, for example, Neatan (Merck) [21 — 23]. In order to avoid clogging the spray head with plastic dispersion residue it is recommended that it be rinsed through immediately after use with tetrahydrofuran or that disposable jets be employed [24]. 

Brauer, Stansbury Flowers (1986) modified these cements in several ways. The addition of various adds - acetic, propionic, benzoic etc. -accelerated the set. The use of zinc oxide powders coated with propionic add improved mixing, accelerated set, reduced brittleness and increased compressive strength from 63 to a maximum of 72 MPa. The addition of plasticizing agents such as zinc undecenylate yielded flexible materials. Incorporation of metal powders had a deleterious effect and greatly increased the brittleness of these cements. The addition of fluorides was not very successful, for fluoride release was not sustained. 

Ionotropic glutamate receptors mediate fast excitatory neurotransmission in practically all areas of the central nervous system (CNS). They are also critical for both the induction and expression of synaptic plasticity, and have been implicated in diverse pathological conditions, such as epilepsy, ischemic brain damage, anxiety, and addiction. There are three subtypes of ionotropic glutamate receptors that are named after their high-affinity agonists as a-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA), N-1nethyl-D-aspartate (NMDA), and kainate (KA) receptors (1). 

While other organic esters are commercially available, namely cellulose butyrate and cellulose propionate, by far the most widely used is cellulose acetate, which is available as plastics, in films, sheets, fibers, and lacquers. Cellulose acetate is used in the manufacture of display packaging and as extruded film for decorative signs, and to coat a variety of fibers. Injected molded products include toothbrush handles, combs, and brushes. It is also used in lacquers and protective coatings for metal, glass, and paper. Cellulose acetate films are used in reverse osmosis to purify blood, fruit juices, and brackish water. Some eyeglass frames are... 

Lactose is readily fermented by lactic acid bacteria, especially Lactococcus spp. and Lactobacillus spp., to lactic acid, and by some species of yeast, e.g. Kluyveromyces spp., to ethanol (Figure 2.27). Lactic acid may be used as a food acidulant, as a component in the manufacture of plastics, or converted to ammonium lactate as a source of nitrogen for animal nutrition. It can be converted to propionic acid, which has many food applications, by Propionibacterium spp. Potable ethanol is being produced commercially from lactose in whey or UF permeate. The ethanol may also be used for industrial purposes or as a fuel but is probably not cost-competitive with ethanol produced by fermentation of sucrose or chemically. The ethanol may also be oxidized to acetic acid. The mother liquor remaining from the production of lactic acid or ethanol may be subjected to anaerobic digestion with the production of methane (CH4) for use as a fuel several such plants are in commercial use. 

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