US2478654A - Plastic bituminous material and method of making the same - Google Patents

Description

1949? G. CROYERE 2,478,654

PLASTIC BITUMINOUS MATERIAL AND METHOD OF MAKING THE SAME Filed April 9, 1946 o 5 o is 2'0 25 .30 35 .4o 45 III INVENTOR. G. Cro yere Patented Aug. 9, 1949 v 2,478,654. r p w PLASTIC nirnmnovstrsrsnmpnpn METHOD OFMAKINGFTHESAME V Ghi siain Groyere, DecazeviIlm France assiignor ;LouvroiI-Montbard-Aulnoye, Paris, France; a 7 body corporate of-France p tippifcationtfipril 9, 1s4ai senai' No. seem iImFraI'roe; October-m me Section 1, Piibflc Law 69ft,v s in-sesame Patent expires October 275.1964

Coal tar' pitch ais bbttiiried'bfthie distillation "of the tar "from cokeplantsi town-gasplants; gas producers, etc., 'is frequentlyuse'd for the production of water-tight Iii-rings on roofs, terraces,

metal parts to be buried or immersed, etc.

In most of such applicationsfthe said pitch 'sufiers from the 'ma jorinconvenience that it "is exceedingly sensitive; to variations in temperature. 'Wh'ile'beingvery'brittle in the cold,'it will soften as soonas temperature'rises somewhat; Moreover, itfissubject to flow considerably; that is, it will undergo deformation by the effector its own weight-'when'ever' it is "laid in a layer of substantial thickness sloping towards the horizontal'. This phenomenon particularly evident at those temperaturesat' which the product is comparatively soft', although'it is still very appreciable at temperatures at which pitch has taken a hard and brittle character. Last, pitch is=-sub1ieot to-the phenomenon known as" aging. A layer of" pitch when left exposed: "tothe action of the airwill crack rapidly. Such cracks frequently reach a considerable depth'an'd} thus in"- pair the Water-tightness of-the lining; The pitch assumes an increasingly hard and brittle charac ter and the structureis -i'n'f'al1ib1y doomed to destruction unless'the"'aging' oiithe lining" iscured intime. 7

These peculiarities muster-any restrict the field of application for pitch, inasmuch asfthey involve among others *the following "inconven- 1 Trimming wilrcrairbythe action or cold (which seems to'be -(iiie "to 'thefact thatpitch becomes very brittle in thecold andfthus can n'o or "mama" seen-e1" fabrics, cardboard, felt and-"the meme chief ffiect "of the addition of fluxes or fillers tO-Iiith i's to modify the properties of the latter "with a View toadapt them to the required conditions ofuse, but "it 'has' no decisive effect upon the properties discussed above, Viz-g: temperature" sensitiveness, aging, flowing; s V 1 -"Siini'lar properties; re- 'fbund althou h to a much less degree-'ih pitc manufacture notably by oxidation from miherai' oil's, soth'at same generally is preferred to "-coaltar 'p'itc'h for waterproofing and "anticorrosiye- 'purposes. 'However, the cost of such products is much higher. I

New applicant has found th'altit' is possible to correct in a; very-easiest manner theabove m'entioned drawbacks in the case 'oicoalta'r pitch by means of awerysirnple maustnai method so as to-obtain reconstitutedor reformed pitches, the properties of wl'flch approximate very closely those'of' mineral"oil pitches while their cost price is much less thantha't ofsafiiiminera-l oil pitches and the-said improved reeo'nstitutedlpitches may be advantageously applied a large number of cases and IIIOIBrPflFl-MCHIFtElM-fGI' fluid-tight structures. I

It. has already been proposed to incorporate 'anthracenepaste to bbal t'afpitcfi, Said anthra= cene paste being the solid" product separating a'iter' "coplingironr certai oils obtained through distillation 'or coaltar "tar obtained in gas plarits3xtfoke1piarits: or' gaszeproducers; But such anthracene paste was used-heretofore only as a fiux th'at isfwith ei view to obtaininga lowering of thersofteningipoint fihe original pitch; 'Such prior mixtures serve ini particular for the production of iuelagg lomerates such'as coal duster brown coal dust briquettes and the like;

However, the,applicanthasiounci that the properties of 'pitch-anthracene paste mixtures undergo unekp'ectedfbut. highly valuable alteratibn's dependingjon thelrespect'i /e: percentages 'o'f pitchand anthracenepastee g The invention is m areteam =theaccompanying drawings in which Fig. 1 is a diagrammane vrew illustrating the general course of thevmelting curve, the percentages of anthraceneanct themi'eltihgcpoints of t'he mixture, and -t rFie-i #2 isea ternary v diagram with the curve defining the proportions between the pitch anthracenea'ndthe' coal' tar'oil'; r

In particular if the isbft'efiin'g;.poiiit ofa mix 'ture oii'coamarpitcn; an-a aifthracene paste 'is of the American Society for Testing Material, it is found that said point of softening first decreases down to an approximative content of 15% of anthracene paste. It then rises suddenly until said content reaches a value comprised between '30 and 40% and it varies subsequently only in a. very slow manner (see Fig. 1). It is apparent that the constitution of the mixture is clearly different according to the proportions to be foreseen for the two components by reason of the modifications mentioned hereinabove as concerns the physical and mechanical properties of the mixture which properties are entirely different to either side of the point marked Bin Fig. 1;; But the point that should be primarily remarked consists in that a little before the point marked C on the curve, that is the point beyond which the variations in the softening temperature becomes very slow, the mixture obtained shows properties approximating closely those of mineral oil pitches. The applicant has'also found that a new physieal constituent will result from an infinity of proportions between pitch, anthracene and coal tar oil that are defined by curve the of the ternary diagram shown in Fig. 2. In the said diagram apex I represents a highly dry pitch (with a K.S. melting point higher than 100 C.), II represents an ordinary anthracene oil and III the crystal mass separated as explained above, then carefully drained and finally stripped of every trace of mother oil by extraction with a suitable solvent such as ethyl alcohol. Points on curve abc indicate the melting temperatures of the corresponding mixtures.

The following examples are illustrative of the properties that can be obtained by the method described hereinbefore. a

The following materials are used:

Per cent Coke plant tar pitch M. P. (K. S.) 70 C. 65.5 Raw drained commercial anthracene from the fraction 290380 C., containing 32% of ethancl-soluble oils and melting between 110 and 130 C. in the de-oiled state 34.5

The mixture is melted. The product obtained possesses the following properties:

M. P. (K. S.) 80 C. Penetration ASTM under 100 g. load at- Flowing: Completely null up to 65 C. Slight between 65 and 70 C.

Aging: With the above product aging makes itself noticeable by the formation of shallow and consequently wholly harmless wrinkles, even after three years exposure to the sun and inclemencies.

A better appreciation of the importance of this invention will be had from the following statement, given by way of example, of the characteristics of a good fluxed coal tar pitch and a mineral oil pitch which are similar as to the results of the penetration test at 25 C.

1.-C'oaZ tar pitch M. P. (K. S.) 55 C. ASTM penetration test (100 g.) at- 25 C 25 45 C -Too large to be measurable.

Flowing: The pitch has flowed completely at 25 C. It even fiows at C.

Aging: Deep cracks reaching the whole thickness of the pitch layer after exposure of the same.

Moreover, the applicant has found that the product obtained in the performance of this method can be improved considerably by physical treatments to be carried out'upon either the product itself or the raw materials involved in the production thereof.

The said physical treatments are those which are usually employed for resinifying the oily and low-boiling constituents of pitch and generally of coal tar derivatives. Such are: l. Oxidation by air-blowing, 2. Chlorination with the aid of a mixture of chlorine with air or of chlorine alone,

resins whose molecules arecapable of providing linkages between the molecules of the oils present,

such as resins belonging to the vinyl, or the acryl, or the methacryl, or the styrene series.

Briefly stated, every substance capable of flxing in larger molecular structures those too lowboiling compounds whose escape is one of the main causes of aging can be used.

The applicant does not intend to protect the application of the above-enumerated treatments to every coal'tar oil and pitch but only to the above-described product and to the raw terials involved in the production thereof.

The examples givenhereinafter are illustrative of the properties that can be obtained by resinification. of pitch-oil-anthracene mixtures defined in the above. For the sake of simplicity the said mixture will be referred to as product No. 1."

Example 1. Blowing product No. 1 by means of an air stream passedthrough the molten mass at the rate of half a liter per kilogram of material and per minute. 7

Temperature of the melt: 190 C. Duration: 4 hours.

Example 2.Admixing product No. 1 with 0% by weight of anthracene oil and blowing the mixture with a mixture of air with 5% by volume of chlorine fed at the rate. of half a liter per kilogram of material and per minute.

Temperature of the melt: 190' C. Duration: 4 hours.

Example 3.-Treating product No. 1 for 3 hours at a temperature of 220 C. with /20 of its own weight of sulfur flour.

Example 4.Admixing product No. 1 with 2% by weight of anhydrous iron chloride and heating the mixture for 3 hours at 250 C.

Example 5.-Admixing product No. -1 with 2% by weight of polyvinyl chloride and heating the mixture for 2 hours at C.

Example 6.-Admixing product No. 1 with 5% of polyvinyl chloride and heating the mixture for 2 hours at 130 C.

The treatments defined by the above examples are effective to increase the stability of the product and to counteract aging.

What I claim as my invention and desire to secure by Letters Patent is:

1. A plastic bitumen-like material of very low temperature sensitivity and flow capacity constituted by a mixture of about 65% of coal tar pitch with about 35% by weightof commercial anthracene paste. 2. A method forproducing a bitumen-like ma- 5 terial having a very low flow capacity and temperature sensitivity, consisting in melting and mixing together about 65 parts of coal tar pitch by weight with about 35 parts 'by weight of raw commercial anthracene paste.

3. A method for producing a bitumen-like material having a very low flow capacity and temperature sensitivity, consisting in melting and mixing together about 65 parts of coal tar pitch by weight with about 35 parts by weight of raw commercial anthracene paste and incorporating to the mixture a filler substance.

4. A method for producing a bitumen-like material having a very low flow capacity and temperature sensitivity, consisting in melting and mixing together about 65 parts of coai tar pitch by weight with about 35 parts by weight of raw commercial anthracene paste and oxidizing the molten mixture through blowing.

GHISLAIN CROYERE.

REFERENCES CITED The following references are of record in the file of this patent:

6 UNITED STATES PATENTS riumber Name Date 924,086 Meadows et a1. June 8, 1909 1,286,261 Henderson May 14, 1918 2,059,051 Sparks Oct. 27, 1936 2,093,450 Jacobsohn Sept. 21, 1937 2,095,190 Heuscher Oct. 5, 1937 2,220,714 Hersberger Nov. 5, 1940 2,281,728 Thelen May 5, 1942 2,287,511 Burk et a1. June 23, 1942 2,297,455 Brautigam et a1. Sept. 29, 1942 2,348,832 Mauch et a1 May 16, 1944 2,395,853 Fair Mar. 5, 1946 FOREIGN PATENTS Number Country Date 1,428 Great Britain, 1914 Apr. 19, 1915 216,245 Great Britain May 29, 1924 216,602 Great Britain June 5, 1924 OTHER REFERENCES Abraham, Asphalts and Allied Substances, 4th Edition, pages 366 and 367, published by D. Van Nostrand Co.

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