Classifications

• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
  • C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
  • C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
  • C23F11/10—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using organic inhibitors
  • C23F11/12—Oxygen-containing compounds
  • C23F11/122—Alcohols; Aldehydes; Ketones
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
  • D01F2/24—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives
  • D01F2/28—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives from organic cellulose esters or ethers, e.g. cellulose acetate
  • D01F2/30—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives from organic cellulose esters or ethers, e.g. cellulose acetate by the dry spinning process

Definitions

• the present invention relates to. the prevention of corrosion of metals. by solutions of. organic acid esters of cellulose in halogen-containing organic solvents. More particularly, it relates to novel. processes for preventing such. corrosion. by incorporation inthe solutions ofspecialstabilizing agents.
• esters may be dissolved in halogen-containing organic solvents and. by. way of: illustration, cellulose t-riacetate is dissolved. in methylene chloride which may also contain minor amounts of co-solvents for the ester such as methanol, ethanol, isopropanol or the like, as well as smallamounts of water-
• This solution or dope is then dry spun into filamentary cellulose, triacetate, the solvent. being evaporated by a currentof Trust air followed by recovery and purification prior tov re-use. The spinning;
• Another. object is, to provide a, solution of cellulose triacetate in methylene chloride, which solution can be dry spun without rapid corrosion of the spinning jet.
• a stabilizer which in hibits corrosion of metallic members.
• the stabilizers must satisfy certain requirements in order to be suitable for use, viz., they must themselves be non-corrosive, they should not have any particular afiinity for the cellulose ester lest they contaminate articles produced therefrom, they should not deleteriously affect the physical properties of the cellulose esters, under conditions of use they should not endanger the operators, they should not irritate or sensitize the skin when worn and preferably they should be sufficiently inexpensive so that their cost will be compensated for by savings in the replacement cost of metal equipment or by improvements in the properties of the esters as a result of elimination of metallic contaminants.
• acetylenic alcohols are effective in avoiding the corrosion of metals by solutions. or organic acid esters of cellulose in halogen-containing organic solvents.
• the lower acetylenic alcohols such as 1,4-butynediol and especially propargyl alcohol (Z-propymL-ol). are. preferred.
• The. stabilizers will exert some beneficial action even in the smallest amounts but for appreciable inhibition they should be. present in at least. about 0.005% by weight of the. solution.
• at least about 0.01% by weight is employed and preferably at least about 0.05%. As much as 0.5% or. even more can be used but since corrosion is substantially completely eliminated with lesser amounts there isrnopoint in adding more stabilizer than is necessary.
• The. solvent of the cellulose ester solution can be any halogenated organic. solvent but thepreferred solvents are chlorine-substituted lower alkanes. such as methylene. chloride, .ethylene dichloride, and the like. These may contain. minor amounts of: co-solvents or non-solvents for the esters, dependingupon the properties desired forv the composition and the subsequent treatments towhich. it will be subjected.
• the methylene chloride solvent may contain as much as 20% by weight of volatile alcohols suchas methanol, ethanol,
• water Willdecrease the solubility of the ester in the solvent, small amounts can be tolerated. The stabilizing actionwill-berealized even inthe presence of water.
• Organic acid esters of cellulose which can be used are preferably the lower alkanoic acid esters such as the acetate, propionate, butyrate, acetate-propionate, acetatebutyrate, and the like. While the invention is applicable to any esters which will dissolve in the indicated solvents, excelleut results are achieved when using a cellulose acetate having an acetyl content in excess of about 59.5% and preferably 61.5% by weight calculated as acetic acid. Such esters are substantially fully acetylated, i.e., free of unreacted hydroxy groups, and are hereinafter referred to as cellulose triacetate although a small residue of unreacted hydroxy groups may be present.
• Such esters are substantially fully acetylated, i.e., free of unreacted hydroxy groups, and are hereinafter referred to as cellulose triacetate although a small residue of unreacted hydroxy groups may be present.
• the present invention is particularly useful in the dry spinning of solutions of cellulose triacetate in methylene chloride-methanol such as are disclosed in copending US. application Serial No. 566,088, filed February 17, 1956, by Robert K. Davies and Arnold J. Rosenthal.
• the solutions there described comprise cellulose acetates having an acetyl value in excess of 59.5% by weight expressed as acetic acid (herein referred to as cellulose triacetate) dissolved in methylene chloride-methanol to a concentration of above 15% and preferably from 17 to 27%.
• the methylene chloride can range upwards 3 from 80% of thecombined weights of methylene chloride and methanol with about 90% or more preferred.
• These solutions generally contain small amounts of water, from about 0.3% of the weight of the solution up to the amount which will create turbidityfalthou'gh preferably water is present in no more than 60% by weight of the'amount which will create turbidity.
• the amount of water which will create turbidity will vary with the composition of the solution. With the minimum concentration of 15% by weight of cellulose triacetate in'the solution and about of methanol in the solvent the turbidity point will correspond to about 1.7% of water.
• propargyl alcohol is especially desirable. During spinning the propargyl alcohol is vaporized along with the solvent and the amount adhered to the cellulose triacetate is extremely small. Any small residual amounts will be removed during the wet treatments to which fabrics made from said filamentary materials are normally subjected.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Textile Engineering (AREA)
• Artificial Filaments (AREA)

Priority Applications (2)

Applications Claiming Priority (1)

Publications (1)

Family

ID=24658379

Family Applications (1)

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Cited By (4)

Citations (1)

• 0
  • BE BE635269D patent/BE635269A/xx unknown
• 1957
  • 1957-05-31 US US662601A patent/US2892725A/en not_active Expired - Lifetime

Patent Citations (1)

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