Title of Invention

"BITUMENT POLYMER COMPOSITIONS WITH IMPROVED STABILITY"

Abstract Bitumen/polymer compositions with improved stability, comprising a bitumen or mixture of bitumens and, counted as weight of the bitumen or mixture of bitumens, 0.3% to 20% of at least one primary polymer chosen from the group made up of the homopolymers of conjugated dienes, copolymers of conjugated dienes with each other, polynorbornenes, polyisobutylenes, butyl rubber, homopolymers of C2-C4, olefins, copolymers of ethylene and of propylene, terpolymers of ethylene, of propylene and of a diene or of a C4-C12 alpha-olefin and copolymers of ethylene and of at least one monomer A of formula where R1 denotes H, CH3 or C2H5 and R2 denotes a -COOR5, -OR5, -OOCR6 or phenyl radical with R5 denoting a C1-C10 alkyl and R6 denoting H or a C1-C3 alkyl, the said compositions being characterized in that they additionally contain, counted as weight of the bitumen or mixture of bitumens, 0.01% to 12% of at least one olefinic polymer containing epoxy or COOH functional groups, chosen from the copolymers containing, by weight, x% of units originating from ethylene or propylene, y% of units originating from one or more abovementioned monomers A, z% of units originating from at least one monomer B of formula and v% of units originating from one or more monomers C which differ from the monomers A and B, with R1 having the abovementioned meaning, R3 denoting H, -COOH or -COOR5, R4 denoting a- radical, R5 being a C1-C10 alkyl radical and x, y, z and v denoting numbers such that 40 ≤ x s 99.9, 0 ≤ y ≤ 50, 0.1 ≤ z ≤ 20 and 0 ≤ v s 15 with x+y+z+v= 100. and optionally comprising 1% to 40% by weight of the bitumen or mixture of bitumens, of a flux.
Full Text The invention relates to bitumen/polymer composi-tions Which have an improved stability reflected, in particular, in a very good storability when hot and in excellent mechanical properties. It further relates to the application of the said compositions to the production of linings and in particular of road surface dressings, of bituminous mixes or else of waterproof facings. It is known to use these bituminous compositions as linings for various surfaces and in particular as road surface dressings, on condition that these compositions have a certain number of essential mechanical properties.
These mechanical properties are assessed, in practice, by determining, using standardized tests, a series of mechanical characteristics, the most frequently employed of which are the following:
- softening temperature (RBT), expressed in °C
and determined by the ring-and-ball test defined by NF
standard T 66008,
- brittleness point or Fraass point, expressed in
°C and determined according to IP standard 80/53,
- penetrability, expressed in units of 0.1 mm and
determined according to NF standard T 66004,
- tensile rheological characteristics determined
according to NF standard T 46002 and comprising the
quantities:
yield stress σy in bars,
yield elongation y in %,
breaking stress σb in bars,
elongation at break b in %.
In general, conventional bitumens do not simulta-neously exhibit all of the required properties and it has been known for a long time that the addition of various polymers to these conventional bitumens allows the mechanical properties of the said bitumens to be favour-ably modified and makes it possible to form bitumen/polymer compositions which have mechanical properties which are improved in relation to those of bitumens alone.
The polymers liable to be added to the bitumens may be elastomers such as polyisobutylene, polyisoprene,

polybutadiene, polychloroprene, butyl rubber, random ethylene/propylene (EP) copolymers, random ethylene/pro-pylene/diene (EPDM) terpolymers, polynorbornene or else plastomers such as polypropylene, polyethylenes, ethylene/vinyl acetate copolymers, ethylene/methyl acryl-ate copolymers and ethyl/butyl acrylate copolymers.
The bitumen/polymer compositions based on a bitumen or mixture of bitumens and on one or more polymers of the abovementioned type have a limited stability when stored. Demixing takes place fairly rapidly between the bituminous phase and the polymer phase, the result being a deterioration in the physicomechanical properties of the said compositions after a relatively short storage period.
It has been found that the incorporation of olefinic polymers carrying epoxy or COOH functional groups in bitumen/polymer compositions consisting of a bitumen or mixture of bitumens and one or more polymers such as the abovementioned appreciably improves the stability of the said compositions when stored and thereby ensures the maintenance of, or even an improve-ment in, their physicomechanical characteristics.
The subject-matter of the invention is bitumen/ polymer compositions with improved stability, comprising a bitumen or mixture of bitumens and, counted as weight of the bitumen or mixture of bitumens, 0.3 % to 20 % and more particularly 0.5 % to 10 % of at least one primary polymer chosen from the group made up of the homopolymers of conjugated dienes, copolymers of conjugated dienes with each other, polynorbornenes, polyisobutylenes, butyl rubber, homopolymers of C3-C4 olefins, copolymers of ethylene and of propylene, terpolymers of ethylene, of propylene and of a diene or of a C4-C12 alpha-olefin and copolymers of ethylene and of at least one monomer A of


formula CH2 = C-R1 R2, where R1denotes H, CH3 or C2H5 and R2

denotes a -COORb, -OR5/ -OOCR6 or phenyl radical with R5 denoting a C1-C10 and preferably C1-C6 alkyl and R6 denot-

ing H or a C1-C3 alkyl, the said compositions being characterized in that they additionally contain, counted as weight of the bitumen or mixture of bitumens, 0.01 % to 12 % and preferably 0.1 % to 5 % of at least one olefinic polymer containing epoxy or COOH functional groups, chosen from the copolymers containing, by weight, x % of units originating from ethylene or propylene, y % of units originating from one or more abovementioned monomers A, z % of units originating from at least one

monomer B of formula R3 - CH = C-R1,R2 and v % of units
originating from one or more monomers C which differ from the monomers A and B, with R1. denoting H, CH3 or C2H5/ R3
denoting H, COOH or COORj, R4 denoting a -COOH, -COO-CH2-CH-CH2
or -O-CH2-CH-CH2, radical, R5 being a C1-C10 and preferably
C1-C6 alkyl radical and x, y, z and v denoting numbers such that 40 s x s 99.9, 0 s y s 50, 0.1  z  20 and 0 s v s 15 with x + y+z+v = 100.
In the abovementioned copolymers x, y, z and v are preferably such that 50 s x s 99.5, 0 s y s 40, 0.5  z s 15 and 0  v s 10 with x+y+z+v= 100.
The monomers A of formula CH2 = C-R1,R2, which
provide, in the copolymer containing them, the units -CH2 - C- are chosen in particular from vinyl formate,
vinyl acetate, vinyl propionate, vinyl butyrate, vinyl ethers CH2=CH-0-R5 where R5 is a C1-C10 and preferably C1-C6 alkyl radical such as methyl, ethyl, propyl or butyl, alkyl acrylates and methacrylates of formula CH2=CH-COOR5

CH3
and CH2 = C - COOR5 respectively where R5 has the meaning
given above.
The monomers B of formula R, - CH = C-R1,R2 which

in the functionalized olefinic copolymer provide the

units -C- C- are chosen in particular from maleic acid
and its anhydride, acrylic acid, methacrylic acid, alkyl hydrogen maleates of formula HOOC-CH=CH-COOR, where R7 is a C1-C6 alkyl radical such as methyl, ethyl, propyl or butyl, glycidyl acrylates and methacrylates of formula
CH2 = CH-COC-CH2-CH-CH2 , and CH2 = C -COO-CH2-CH-CH2
respectively, vinyl alcohol and glycidyl vinyl ether of
0
A formula CH2 = CH—O-CH2—CH-CH2 .
The monomers C, the presence of which in the olefinic copolymer is optional, are monomers which can be polymerized by a radical route and which differ from the monomers A and B, like, for example, CO, SO2 and acrylonitrile.
In particular, the olefinic copolymers carrying epoxy or COOH functional groups are chosen from:
(a) random copolymers of ethylene and of a
monomer B chosen from acrylic acid, methacrylic acid,
maleic acid or its anhydride, glycidyl acrylate and
glycidyl methacrylate, which contain, by weight, 80 % to
99.7 % and preferably 85 % to 99.5 % of ethylene;
(b) random terpolymers of ethylene, of a monomer
A chosen from vinyl acetate and alkyl acrylates or

methacrylates with a C1-C6 alkyl residue such as methyl, ethyl, propyl, butyl or hexyl, and of a monomer B chosen from acrylic acid, methacrylic acid, maleic acid or its anhydride, glycidyl acrylate and glycidyl methacrylate, which contain, by weight, 0.5 % to 40 % of units originating from the monomer A and 0.5 % to 15 % of units originating from the monomer B, the remainder being made up of units originating from ethylene; and
(c) the copolymers resulting from the grafting of a monomer B chosen from acrylic acid, methacrylic acid, maleic acid or its anhydride, glycidyl acrylate and glycidyl methacrylate, onto a substrate consisting of a polymer chosen from polyethylenes, especially low density polyethylenes, polypropylenes and the random copolymers of ethylene and of vinyl acetate or of ethylene and of alkyl acrylate or methacrylate with a C1-C6 alkyl residue such as methyl, ethyl, propyl, butyl or hexyl, which contain, by weight, 40 % to 99.7 % and preferably 50 % to 99 % of ethylene, the said graft copolymers containing, by weight, 0.5 % to 15 % of graft units originating from the monomer B.
Particularly preferred are the olefinic copolymers chosen from:
(i) random terpolymers of ethylene, of alkyl acrylate or methacrylate with a C1-C6 alkyl residue such as methyl, ethyl or butyl, and of maleic anhydride, which contain, by weight, 0.5 % to 40 % of units originating from alkyl acrylate or methacrylate and 0.5 % to 15 % of units originating from maleic anhydride, the remainder being made up of units originating from ethylene;
(ii) random terpolymers of ethylene, of alkyl acrylate or methacrylate with a C1-C6 alkyl residue such as methyl, ethyl or butyl, and of glycidyl acrylate or methacrylate, which contain, by weight, 0.5 % to 40 % of units originating from alkyl acrylate or methacrylate and 0.5 % to 15 % of units originating from glycidyl acrylate or methacrylate, the remainder being made up of units originating from ethylene;
(iii) low density polyethylenes grafted with

maleic anhydride and polypropylenes grafted with maleic anhydride, which contain, by weight, 0.5 % to 15 % of graft units originating from maleic anhydride;
(iv) low density polyethylenes grafted with glycidyl acrylate or methacrylate and polypropylenes grafted with glycidyl acrylate or methacrylate, which contain, by weight, 0.5 % to 15 % of graft units orig-inating from the glycidyl derivative.
The olefinic copolymers carrying epoxy or COOH functional groups, employed for producing the bitumen/ polymer composition advantageously have molecular masses such that the melt index of the said copolymers, determined according to ASTM standard D 1238 (test carried out at 190°C under a 2.16 kg load) has a value, expressed in grams per 10 minutes, of between 0.3 and 3000 and prefer-ably between 0.5 and 900.
The bitumen or mixture of bitumens which is employed for implementing the process according to the invention is chosen advantageously from the various bitumens which have a kinematic viscosity at 100°C of between 0.5 x 10-4 mVs and 3 x 10-2 m2/s and preferably between 1 x 10-4 m2/s and 2 x 10-2 m2/s. These bitumens may be bitumens from direct distillation or from distillation at reduced pressure or else asphaltic or semiasphaltic bitumens, residues from deasphalting with propane or with pentane, viscoreduction residues, or even some petroleum cuts or mixtures of bitumens and of vacuum distillates or else mixtures of at least two of the products which have just been listed. Besides a kinematic viscosity included within the abovementioned ranges, the bitumen or mixture of bitumens employed in the process according to the invention advantageously has a penetrability at 25°C, defined according to NF standard T 66004, of between 5 and 800 and preferably between 10 and 400.
The primary polymer may be in particular poly-butadiene, polyisoprene, polychloroprene, carboxylated or hydroxylated polybutadiene, carboxylated or hydroxylated polyisoprene, butadiene/isoprene copolymers, polynorbor-nene, polyisobutylene, butyl rubber, high density

polyethylene, low density poly-ethylene, polypropylene, polybutene, random ethylene/ propylene (EP) copolymers, random ethylene/propylene/ diene (EPDM) terpolymers, ethylene/vinyl acetate copolymers, ethylene/C1-C6 alkyl acrylate copolymers, especially ethylene/methyl acrylate copolymers and ethylene/butyl acrylate copolymers, and ethylene/C1-C6 alkyl methacrylate copolymers, especially ethylene /ethyl methacrylate copolymers and ethylene/butyl methacrylate copolymers, ethylene/styrene copolymers and ethylene/ butene/styrene copolymers.
If appropriate, at least a proportion of the primary polymer may consist of ground waste of the said polymer.
The bitumen/polymer composition is prepared by bringing into contact the primary polymer(s) and the olefinic polymer(s) functionalized with epoxy or COOK groups with the bitumen or mixture of bitumens, in proportions chosen within the ranges defined above, the operation being carried out at temperatures of between 100°C and 230°C, more particularly between 120°C and 190°C, and with stirring, for a period of at least 10 minutes, generally of the order of some tens of minutes to a few hours and, for example, from 10 minutes to 8 hours and more particularly from 10 minutes to 5 hours, to form a homogeneous mass constituting the bitumen/poly-mer composition. The primary polymer can be incorporated into the bitumen or mixture of bitumens before or after the olefinic polymer containing epoxy or COOH groups, it being possible for a simultaneous incorporation also to be envisaged.
While it is being made up, the bitumen/polymer composition may have further added to it from 1 % to 40 % and more particularly from 2 % to 30 %, by weight of the bitumen, of a flux which may consist, in particular, of a hydrocarbon oil exhibiting a distillation range at atmospheric pressure, determined according to ASTM standard D 86-67, of between 100°C and 600°C and situated more especially between 150°C and 400°C. This hydrocarbon oil, which may be in particular a petroleum cut of aro-

matic nature, a petroleum cut of naphtheno-aromatic nature, a petroleum cut of naphtheno-paraffinic nature, a petroleum cut of paraffinic nature, a. coal oil or else an oil of vegetable origin, is sufficiently "heavy" to limit evaporation at the time of its addition to the bitumen, and at the same time sufficiently "light" to be removed as much as possible after spreading of the bitumen/polymer composition containing it, so as to recover the same mechanical properties which the bitumen/polymer composition prepared without employing a flux would have exhibited after being spread hot. The flux may be added to the reaction mixture formed from the bitumen, the sulphur-crosslinkable elastomer and the sulphur-donor coupling agent at any time during the making up of the said reaction mixture, the quantity of flux being chosen, within the ranges defined above, to be compatible with the final desired use on the work site.
The mixture based on bitumen or mixture of bitumens, on polymer or primary polymers, on olefinic polymer(s) carrying epoxy or COOH groups and optionally on a flux, which gives rise to the bitumen/polymer composition, can also contain one or more additives capable of reacting with the epoxy or COOH groups of the functionalized olefinic polymer. These reactive additives may be in particular primary or secondary amines, especially polyamines, alcohols, especially polyols, acids, especially polyacids, or metal salts.
Reactive additives of the amine type are, for example, aromatic diamines such as 1,4-diaminobenzene, 2,4-diaminotoluene, diaminonaphthalene, bis (4-aminophenyl) sulphone, bis(4-aminophenyl) ether, bis (4-aminophenyl)methane, aliphatic or cycloaliphatic diamines such as those of formula H2N-R13-NH2 where R13 denotes a C2-C12 alkylene or C6-C12 cycloalkylene radical, for example ethylenediamine, diaminopropane,- diamino-butane, diaminohexane, diaminooctane, diaminodecane, diaminododecane, diaminocyclohexane, diaminocyclooctane, diaminocyclododecane, polyethylenepolyamincs or polypropylenepolyamines such as diethylenetriamine.

triethylenetetramine, tetraethylenepentamine, dipropyl-enetriamine, or else fatty amines or polyamines, that is to say amines or polyamines containing a C12-C18 alkyl or alkenyl radical bonded to the nitrogen atom of an amine group.
Reactive additives of the alcohol type are, in particular, polyols such as diols or triols and especially diols of formula HO-R14-OH, where R14 denotes a hydrocarbon radical, especially a C2-C18 alkylene, C6-C8 arylene and C6-C8 cycloalkylene radical, and polyether-diols of formula HO [CqH2qO] rH where q is a number ranging from 2 to 6 and especially equal to 2 or 3 and r is a number at least equal to 2 and ranging, for example, from 2 to 20. Examples of such polyols are ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, hexanediol, octanediol and polyhydroxylated polybutadiene.
Reactive additives of the acidic type are, in particular, polyacids of formula HOOC-R14-COOH, where R14 has the meaning given above. Examples of such polyacids are phthalic acid, terephthalic acid, malonic acid, succinic acid, adipic acid, glutaric acid and poly-carboxylated polybutadiene.
Reactive additives of the metal salt type are, in .particular, compounds such as hydroxides, oxides, alco-holates, carboxylates like formates and acetates, methox-ides, ethoxides, nitrites, carbonates and bicarbonates of metals of groups I, II, III and VIII of the Periodic Table of the Elements, especially Na, K, Li, Mg, Ca, Cd, Zn, Ba, Al and Fe.
The quantity of the reactive additive or of the reactive additives which is incorporated into the reaction mixture giving rise to the bitumen/polymer compositions may range from 0.01 % to 10 % and more particularly from 0.05 % to 5 % of the weight of bitumen present in the said reaction mixture.
Besides the reactive additives and the flux, it is also possible to incorporate into the bitumen/polymer compositions, at any time during their formation, addi-

tives which are conventionally employed in bitumen/ polymer compositions, such as promoters of adhesion of the bitumen/polymer composition to mineral surfaces or else fillers such as talc, carbon black and shredded scrap tyres.
When the bitumen/polymer composition contains a flux consisting of a hydrocarbon oil as defined above, the said bitumen/polymer composition can be produced by incorporating the olefinic polymer carrying epoxy or COOH groups and the primary polymer into the bitumen or mixture of bitumens in the form of a master solution of these polymers in the hydrocarbon oil constituting the flux.
The master solution is prepared by bringing into contact the ingredients of which it consists, namely hydrocarbon oil serving as solvent, olefinic polymer containing epoxy or COOH groups and/or primary polymer and, where appropriate, reactive additive, at temperatures of between 10 °C and 170°C and more particularly between 40°C and 120°C and with stirring, for a sufficient period, for example of between 10 minutes and 2 hours, to dissolve the ingredients completely in the hydrocarbon oil.
The respective concentrations of the various ingredients, especially olefinic polymer containing epoxy or COOH groups, primary polymer and, where appropriate, reactive additive, in the master solution can vary quite widely as a function, in particular, of the nature of the hydrocarbon oil employed for dissolving the said ingredients. Thus, the respective quantities of function-alized olefinic polymer and of primary polymer may advantageously represent 1 % to 20 % and 5 % to 30 % by weight of the hydrocarbon oil.
To prepare the bitumen/polymer compositions by making use of the master solution technique, the master solution containing the functionalized olefinic polymer and the primary polymer and, where appropriate, the reactive additives is mixed with the bitumen or mixture of bitumens, the operation being carried out at tempera-

tures of between 100°C and 230°C, more particularly between 120°C and 190°C, and with stirring, this being done, for example, by incorporating the master solution into the bitumen or mixture of bitumens continually stirred at temperatures of between 100°C and 230°C and more particularly between 120°C and 190°C, and the resulting mixture is then kept stirred at temperatures of between 100°C and 230°C, more particularly between 100°C and 190°C, for example at the temperatures employed for producing the mixture of the master solution with the bitumen, for a period of at least 10 minutes, and generally ranging from 10 minutes to 2 hours, to form a reaction product constituting the bitumen/polymer composition.
The quantity of master solution mixed with the bitumen or mixture of bitumens is chosen so as to provide the desired quantities, in relation to the bitumen, of olefinic polymer containing epoxy or COOH groups and the primary polymer, the said quantities being within the ranges defined above.
The bitumen/polymer compositions with improved stability according to the invention can be employed as they are or else diluted with variable proportions of a bitumen or mixture of bitumens or of a composition according to the invention which has different characteristics, to constitute bitumen/polymer binders which have a chosen polymer content which may be either equal to (undiluted composition) or else lower than (diluted composition) the polymer content of the corresponding initial bitumen/polymer compositions. The dilution of the bitumen/polymer compositions according to the invention with the bitumen or mixture of bitumens or with a composition according to the invention of different characteristics can be carried out either directly following the preparation of the said compositions, when a virtually immediate use of the resulting bitumen/polymer binders is required, or else after a more or less prolonged period of storage of the bitumen/polymer compositions, when a postponed use of the resulting bitumen/polymer binders is

envisaged. The bitumen or mixture of bitumens employed for diluting a bitumen/polymer composition according to the invention may be chosen from the bitumens defined above as being suitable for the preparation of the bitumen/polymer compositions.
The dilution of a bitumen/polymer composition with a bitumen or mixture of bitumens or with a second composition according to the invention with a lower polymer content, to form a bitumen/polymer binder with a chosen polymer content which is lower than that of the bitumen/polymer composition to be diluted, is generally carried out by bringing into contact, with stirring and at temperatures of between 100°C and 230°C and more particularly between 120°C and 190°C, suitable proportions of the bitumen/polymer composition to be diluted and of bitumen or mixture of bitumens or of second bitumen/polymer composition according to the invention.
The bitumen/polymer binders consisting of the bitumen/polymer compositions according to the invention or resulting from the dilution of the said compositions with a bitumen or mixture of bitumens or with another bitumen/polymer composition according to the invention, to the desired content of polymer(s) in the said binders, can be applied, directly or after conversion into aqueous emulsion, to the production of road surfacings of the surface lining type, to the production of bituminous mixes which are applied hot or cold, or else to the production of waterproof facings.
The invention is illustrated by the following examples which are given without any limitation being implied.
In these examples quantities and percentages are expressed by weight except when shown otherwise.
In addition, the rheological and mechanical characteristics of the bitumens or of the bitumen/polymer compositions to which reference is made in the said examples, namely penetrability and ring-and-ball soften-ing point, are those defined above.

EXAMPLES 1 TO 6;
Control bitumen/polymer compositions (Examples 1, 2 and 3) and bitumen/polymer compositions according to the invention (Examples 4, 5 and 6) were prepared in order to evaluate and compare their physicomechanical characteristics.
The operation was carried out in the following conditions:
Example 1 (control);
Into a reactor maintained at 175°C and with stirring were introduced 965 parts of a bitumen which had a penetrability, determined according to the terms of NF standard T 66004, in the 50/70 range, and 35 parts of a random ethylene/vinyl acetate copolymer containing 18 % of vinyl acetate and possessing a melt index, determined according to ASTM standard D 1238, which had a value of 150 g per 10 minutes. The contents of the reactor were then kept at 175°C, with stirring, for a period of 2.5 hours, to produce the bitumen/polymer composition. Example 2 (control);
The procedure was as described in Example 1, but with the ethylene/vinyl acetate copolymer being replaced with a random ethylene/butyl acrylate copolymer containing 35 % of butyl acrylate and possessing a melt index, determined according to ASTM standard D 1238, which had a value of 40 g per 10 minutes. Example 3 (control);
The procedure was as described in Example 1, but with the ethylene/vinyl acetate copolymer being replaced with a low density polyethylene possessing a melt index, determined as shown in Example 1, which had a value of 1.2 g per 10 minutes.
Example 4 (according to the invention); Into a reactor maintained at 175 °C and with stirring were introduced 950 parts of the bitumen employed in Example 1, as well as 35 parts of the ethylene/vinyl acetate copolymer employed in Example 1 and 15 parts of an e thy lene/methyl acrylate/glycidyl methacrylate terpolymer containing 24 % of methyl

acrylate and 8 % of glycidyl methacrylate and possessing a melt index (ASTM standard D 1238) which had a value of 6 g per 10 minutes. The contents of the reactor were next kept at 175°C, with stirring, for a period of 2.5 hours, to form the bitumen/polymer composition according to the invention.
Example 5 (according to the invention); The procedure was as described in Example 4, but with the ethylene/vinyl acetate copolymer being replaced with the ethylene/butyl acrylate copolymer employed in Example 2.
Example 6 (according to the invention); The procedure was as described in Example 4, but with the ethylene/vinyl acetate copolymer being replaced with the low density polyethylene employed in Example 3. The penetrability at 25°C (Pen) and the ring-and-ball softening temperature (RBT) were determined on each of the compositions obtained as shown in Examples 1 to 6. In addition, a test for stability in storage at 180°C for 3 days was carried out on each of the bitumen/polymer compositions obtained. This test consists in filling an aluminium tube, of the "toothpaste tube" type, with the composition to be studied and in keeping the tube enclosing the composition at a temperature of 180°C for the chosen storage period, namely 3 days. At the end of the said period the tube is cooled and is then cut into three parts of substantially the same length. The penetration at 25°C and the softening temperature are then determined on the composition in each of the top (upper third) and bottom (lower third) parts of the tube. The difference (Delta X) between the values of the characteristic X in the top part and the bottom part of the tube gives an indication of the stability of the bitumen/polymer composition. The composition is proportionately more stable the smaller the difference "Delta X".
The results obtained are collated in the table below.
In this table the acronyms BT, EVA, EBA, LDPE and

TPO have the following meanings:
- BT: unmodified bitumen with penetrability in
the 50/70 range, employed in the various examples;
- EVA: random ethylene/vinyl acetate copolymer
employed in Examples 1 and 4;
- EBA: random ethylene/butyl acrylate copolymer
employed in Examples 2 and 5;
- LDPE: low density polyethylene employed in
Examples 3 and 6;
TPO: ethylene/methyl acrylate/glycidyl
methacrylate terpolymer employed in Examples 4, 5 and 6.
The EVA, EBA, LDPE and TPO contents of the
compositions are expressed as weight percentages of the
overall quantities of bitumen and polymer(s).
Table

(Table Removed)

In view of the results shown in the table it appears that:
- the base bitumen is stable as expected;
- the bitumen/polymer compositions based on a
bitumen and on a primary polymer are all unstable in


storage (Examples 1 to 3), the bitumen/polymer composition containing polyethylene (Example 3) being the most unstable;
- bitumen/polymer compositions according to the invention, based on a bitumen, a primary polymer and an olefinic polymer which is functionalized, in this case by epoxy groups, (Examples 4 to 6) are appreciably more stable than the control bitumen/polymer compositions (Examples 1 to 3).






We Claim:-
1. Bitumen/polymer compositions with improved stability, comprising a bitumen or mixture of bitumens and, counted as weight of the bitumen or mixture of bitumens, 0.3% to 20% of at least one primary polymer chosen from the group made up of the homopolymers of conjugated dienes, copolymers of conjugated dienes with each other, polynorbornenes, polyisobutylenes, butyl rubber, homopolymers of C2-C4, olefins, copolymers of ethylene and of propylene, terpolymers of ethylene, of propylene and of a diene or of a C4-C12 alpha-olefin and copolymers of ethylene and of at least one monomer A of formula
(Formula Removed)
where R1 denotes H, CH3 or C2H5 and R2 denotes a -COOR5, -OR5, -OOCR6 or phenyl radical with R5 denoting a C1-C10 alkyl and R6 denoting H or a C1-C3 alkyl, the said compositions being characterized in that they additionally contain, counted as weight of the bitumen or mixture of bitumens, 0.01% to 12% of at least one olefinic polymer containing epoxy or COOH functional groups, chosen from the copolymers containing, by weight, x% of units originating from ethylene or propylene, y% of units originating from one or more abovementioned monomers A, z% of units originating from at least one monomer B of
(Formula Removed)
formula and v% of units originating from one or more
monomers C which differ from the monomers A and B, with Ri having
the abovementioned meaning, R3 denoting H, -COOH or -COOR5, R4
denoting a-
(Formula Removed)
radical, R5 being a C1-C10 alkyl radical and x, y, z and v denoting numbers

such that 40 ≤ x≤ 99.9, 0 ≤ y ≤ 50, 0.1 ≤ z ≤ 2 0 and 0 ≤ v ≤ 15 with x + y+z+v = 100.
and optionally comprising 1% to 40% by weight of the bitumen or mixture of bitumens, of a flux.
2. Composition as claimed in claim 1, wherein the primary polymer content represents 0.5% to 10% of the weight of bitumen or mixture of bitumens.
3. Compositions as claimed in Claim 1 or 2, wherein the content of olefinic polymer containing epoxy or COOH functional groups represents 0.1% to 5% of the weight of bitumen or mixture of bitumens.
4. Compositions as claimed in Claims 1 to 3, wherein the olefinic polymer
containing epoxy or COOH groups, the contents x, y, z and v are
such
that 50 ≤ x ≤ 99.5, 0 ≤ y≤ 40, 0.5 ≤ z ≤ 15 and
0 ≤ v ≤ 10 with x+v+z+v= 100.
5. Compositions as claimed in Claim 1 to 4, wherein the monomers A are
chosen from vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate,
vinyl ethers CH2=CH-O-R5, alkyl acrylates of formula CH2=CH-COOR5

(Formula Removed)
and alkyl methacrylates of formula , R5 being aC1-
C10 and preferably C1-C6 alkyl radical, especially methyl, ethyl, propyl or butyl.
6. Compositions as claimed in Claims 1 to 5, wherein the monomers B are
chosen from maleic acid and its anhydride, acrylic acid, methacrylic
acid, alkyl hydrogen maleates of formula HOOC-CH=CH-COOR7 where R7
is a C1-C6 alkyl radical, glycidyl acrylate, glycidyl methacrylate and
glycidyl vinyl ether.

7. Compositions as claimed in Claim 1 to 6, wherein the monomers C are chosen from CO, SO2 and acrylonitrile.
8. Compositions as claimed in Claims 1 to 7, wherein the olefinic polymers containing epoxy or COOH groups are chosen from the group consisting of:
a. random copolymers of ethylene and of a monomer B chosen from
acrylic acid, methacrylic acid, maleic acid or its anhydride, glycidyl
acrylate and glycidyl methacrylate, which contain, by weight, 80%
to 99.7% and preferably 85% to 99.5% of ethylene;
b. random terpolymers of ethylene, of a monomer A chosen from vinyl
acetate and alkyl acrylates or methacrylates with a C1-C6 alkyl
residue such as methyl, ethyl, propyl, butyl or hexyl, and of a
monomer B chosen from acrylic acid methacrylic acid, maleic acid
or its anhydride, glycidyl acrylate and glycidyl methacrylate, which
contain, by weight, 0.5% to 40% of units originating from the
monomer A and 0.5% to 15% of units originating from the
monomer B, the remainder being made up of units originating from
ethylene; and
c. the copolymers resulting from the grafting of a monomer B chosen
from acrylic acid, methacrylic acid, maleic acid or its anhydride,
glycidyl acrylate and glycidyl methacrylate, onto a substrate
consisting of a polymer chosen from polyethylenes, especially low
density polyethylenes, polypropylenes and the random copolymers
of ethylene and of vinyl acetate or of ethylene and of alkyl acrylate
or methacrylate with C1-C6 alkyl residue such as methyl, ethyl,
propyl, butyl or hexyl, which contain, by weight, 40% to 99.7% and
preferably 50% to 99% of ethylene, the said graft copolymers
containing, by weight, 0.5% to 15% of graft units originating from
the monomer B.
9. Compositions as claimed in Claim 8, wherein the olefinic polymers
containing epoxy or COOH groups are chosen from :

i. random terpolymers of ethylene, of alkyl acrylate or methacrylate with a C1-C6 alkyl residue such as methyl, ethyl or butyl and of maleic anhydride, which contain, by weight, 0.5% to 40% of units originating from alkyl acrylate or methacrylate and 0.5% to 15% of units originating from maleic anhydride, the remainder being made up of units originating from ethylene;
ii. random terpolymers of ethylene, of alkyl acrylate or methacrylate with a C1-C6 alkyl residue such as methyl, ethyl or butyl, and of glycidyl acrylate or methacrylate, which contain, by weight, 0.5% to 40% of units originating from alkyl acrylate or methacrylate and 0.5 to 15% of units originating from glycidyl acrylate or methacrylate, the remainder being made up of units originating from ethylene;
iii. low density polyethylenes grafted with maleic anhydride and polypropylenes grafted with maleic anhydride, which contain, by weight, 0.5% to 15% of graft units originating from maleic anhydride; and
iv. low density polyethylenes grafted with glycidyl acrylate or methacrylate and polypropylenes grafted with glycidyl acrylate or methacrylate, which contain, by weight, 0.5% to 15% of graft units originating from the glycidyl derivative.
10. Compositions as claimed in Claims 1 to 9, wherein the olefinic polymers containing epoxy or COOH groups possess a melt index, determined according to ASTM standard D 1238, which has a value, expressed in grams per 10 minutes, of between 0.3 and 3000 and preferably between 0.5 to 900.
11. Compositions as claimed in Claims 1 to 10, wherein the bitumen or mixture of bitumens is chosen from the bitumens which have a kinematic viscosity at 100°C of between 0.5 to 10~4 m2/s and 3 x 10~2 m2/s and preferably between 1 x 10~4 m2/s and 2 x 10"2 m2/s.

12. Compositions as claimed in Claim 11, wherein the bitumen or mixture of bitumens has penetrability at 25°C, defined according to NF standard T 66004, of between 5 to 800 and preferably between 10 and 400.
13. Compositions as claimed in Claims 1 to 12, wherein the primary polymer is chosen from poly butadiene, polyisoprene, polychloroprene, carboxylated or hydroxylated polybutadiene, carboxylated or hydroxylated polyisoprene, butadiene/isoprene copolymers, polynorbornene, polyisobutylene, butyl rubber, high density polyethylene, low density polyethylene, polypropylene, polybutene, random ethylene/propylene (EP) copolymers, random ethylene / propylene/diene (EPDM) terpolymers, ethylene/vinyl acetate copolymers, ethylene/C1-C6 alkyl acrylate copolymers, especially ethylene/methyl acrylate copolymers and ethylene/butyl acrylate copolymers, and ethylene/C1-C6 alkyl methacrylate copolymers, especially ethylene/ethyl methacrylate copolymers and ethylene /butyl methacrylate copolymers, ethylene/ styrene copolymers and ethylene/butane/ styrene copolymers.
14. Compositions as claimed in Claims 1, wherein flux content is more particularly 2% to 30%, by weight of the bitumen or mixture of bitumens, of a flux.
15. Compositions as claimed in Claim 14, wherein the flux consists of a hydrocarbon oil exhibiting a distillation range at atmospheric pressure, determined according to ASTM standard D 86-87, of between 100°C and 600°C and situated more especially between 150°C and 400°C.
16. Compositions as claimed in Claim 15, wherein the hydrocarbon oil is chosen from petroleum cuts of aromatic nature, petroleum cuts of naphtheno-aromatic nature, petroleum cuts of naphtheno-paraffinic

nature, petroleum cuts of parafinnic nature, coal oils and oils of vegetable origin.
17. Compositions as claimed in Claims 1 to 16, wherein the said composition optionally contain one or more additives capable of reacting with the epoxy or COOH groups of the olefinic polymer carrying the said groups, the said reactive additives being in particular primary or secondary amines, especially polyamines, alcohols, especially polyols, acids, especially polyacids or metal salts, especially compounds of metals of groups I, II, III and VIII of the Periodic Table of the Elements.
18. Compositions as claimed in Claim 17, wherein the quantity of reactive additive or of reactive additives which they contain represents 0.01% to 10% and preferably 0.05% to 5% of the weight of the bitumen.
19. A process for preparing the compositions as claimed in Claims 1 to 13 comprises bringing into contact the primary polymer(s) and the olefinic polymer(s) containing epoxy or COOH groups with the bitumen or mixture of bitumens, in the chosen proportions, the operation being carried out at temperatures of between 100°C and 230°C more particularly between 120°C and 190°C and with stirring, for a period of at least 10 minutes, in particular from 10 minutes to 8 hours and more particular from 10 minutes to 5 hours, to form a homogeneous mass constituting the bitumen/polymer composition.
20. A process for preparing the compositions as claimed in Claims 15 or 16 comprises incorporating the olefinic polymer containing epoxy or COOH groups and the primary polymer into the bitumen or mixture of bitumens in the form of a master solution of these polymers in the hydrocarbon oil constituting the flux.

21. A process as claimed in Claim 20, wherein master solution contains, by weight of the hydrocarbon oil, 1% to 20% of olefinic polymer containing epoxy or COOH groups and 5% to 30% of primary polymer.
22. A process for preparing the compositions as claimed in Claim 20 and 21, wherein the compositions are obtained by mixing the master solution with the bitumen or mixture of bitumens, the operation being carried out at temperature of between 100°C and 230°C, more particularly between 120°C and 190°C, and with stirring, and then the resulting mixture being kept stirred at temperatures of between 100°C and 230°C, more particularly between 120°C and 190°C, for a period of at least 10 minutes, in particular ranging from 10 minutes to 2 hours, to form a reaction product constituting the bitumen/polymer composition.
23. Bitumen/polymer compositions as claimed in any of the preceding claims as and when used for the production of bitumen/polymer binder.
24. Bitumen/polymer compositions substantially as hereinbefore described with reference to the forgoing examples.


Documents:

1541-DEL-2005-Abstract-(15-04-2009).pdf

1541-del-2005-abstract.pdf

1541-DEL-2005-Abtract-(31-10-2008).pdf

1541-DEL-2005-Claims-(15-04-2009).pdf

1541-DEL-2005-Claims-(31-10-2008).pdf

1541-del-2005-claims.pdf

1541-del-2005-correspondence-other.pdf

1541-DEL-2005-Correspondence-Others-(15-04-2009).pdf

1541-DEL-2005-Correspondence-Others-(31-10-2008).pdf

1541-del-2005-description (complete).pdf

1541-DEL-2005-Form-1-(31-10-2008).pdf

1541-del-2005-form-1.pdf

1541-DEL-2005-Form-2-(31-10-2008).pdf

1541-del-2005-form-2.pdf

1541-DEL-2005-Form-3-(31-10-2008).pdf

1541-del-2005-form-3.pdf

1541-del-2005-form-5.pdf

1541-DEL-2005-GPA-(31-10-2008).pdf

1541-DEL-2005-Petition-137-(31-10-2008).pdf

1541-DEL-2005-Petition-138-(31-10-2008).pdf


Patent Number 235439
Indian Patent Application Number 1541/DEL/2005
PG Journal Number 31/2009
Publication Date 31-Jul-2009
Grant Date 02-Jul-2009
Date of Filing 14-Jun-2005
Name of Patentee ELF ANTAR FRANCE
Applicant Address TOUR ELF-2 PLACE DE LA COUPOLE, LA DEFENSE 6-92400 COURBEVOIE, FRANCE
Inventors:
# Inventor's Name Inventor's Address
1 JEAN-PASCAL PLANCHE GRAVETAN,38540 SAINT JUST CHALEYSSIN, FRANCE.
2 CLAUDE LACOUR 6 RUE LAMARCK LES CEDRES, 38200 VIENNE, FRANCE
3 PATRICK TURELLO BATIMENT D "LLE GRILLON", 69340 FRANCHEVILLE, FRANCE.
PCT International Classification Number G08L 95/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 96 05827 1996-05-10 France