Moisture-curable compositions and self-adhesive articles containing them
A moisture-crosslinkable adhesive composition using silylated polymers and tackifying resins forms a robust polymeric network, addressing the challenge of maintaining adhesive properties and thermal resistance in high-temperature environments.
Patent Information
- Application Number
- FR2023005668
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-06-06
- Publication Date
- 2024-12-13
AI Technical Summary
Existing adhesive compositions struggle to maintain good adhesive properties and thermal resistance, particularly at high temperatures and under restrictive conditions of temperature and humidity, making them unsuitable for applications in environments exceeding 200°C.
A moisture-crosslinkable adhesive composition comprising silylated polymers, tackifying resins, and specific compounds, which form a three-dimensional polymeric network upon crosslinking, providing excellent adhesive properties and thermal resistance.
The composition achieves high adhesive power and resistance to aging, maintaining performance under extreme temperatures and humidity conditions, with peel strengths exceeding 0.4N/cm and resistance up to 200°C.
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Abstract
Description
Title of the invention: Moisture-crosslinkable compositions and self-adhesive articles containing them FIELD OF THE INVENTION
[0001] The subject of the present invention is a novel moisture-crosslinkable adhesive composition, based on a silylated polymer.
[0002] It also relates to a self-adhesive article, in particular a self-adhesive support which comprises a support layer coated with a self-adhesive layer consisting of said composition in the crosslinked state. Finally, it relates to a method of manufacturing said article. TECHNOLOGICAL BACKGROUND
[0003] Pressure sensitive adhesives (also called self-adhesive glues or PSAs) are substances that give the support layer coated with them immediate tack at room temperature. Often referred to by the English term "tack" or sometimes by the term "stickiness", this immediate tack allows the instant adhesion of said self-adhesive support to all kinds of substrates, under the effect of light and brief pressure. Due to its adhesive power, usually evaluated by a peel test, said self-adhesive support is then firmly fixed to said substrate, by means of an adhesive seal.
[0004] PSAs are widely used for the manufacture of self-adhesive articles, such as for example self-adhesive labels which are fixed on articles for the purpose of presenting information (such as bar code, denomination, price) and / or for decorative purposes, whether in permanent or temporary bonding.
[0005] PSAs are also used for the manufacture of self-adhesive tapes for various uses. Examples include, in addition to the transparent adhesive tape widely used in everyday life: the shaping and assembly of cardboard packaging; the protection of surfaces for painting work, in construction; the fixing and holding of various elements such as panels, bricks, protruding objects, in the construction of buildings or structures; the fixing and holding of metal or plastic or glass parts, flat or having specific profiles, such as electric cables, plastic films, windows, sheets, inscriptions, logos, parts of seats, dashboards, plastic or textile walls, conduits or pipes for circulating fluids, particularly in the transport industry; the bonding of carpets using double-sided adhesive tapes in the construction field.
[0006] For the purpose of manufacturing self-adhesive articles (for example self-adhesive labels and / or tapes), PSAs are generally applied by continuous coating processes to the entire surface of a large (if appropriate printable) support layer, in a quantity (generally expressed in g / m2) and hereinafter referred to as "grammage". The support layer is, for example, paper or a film made of a polymer material with one or more layers. The layer of self-adhesive composition which covers the support layer may itself be covered with a protective anti-adhesive layer (often referred to as a "release liner"), for example made of a silicone film. The multi-layer system obtained is generally packaged by winding in the form of large reels up to 2 m wide and 1 m in diameter, which can be stored and transported.
[0007] These multi-layer systems can be subsequently converted into self-adhesive labels applicable by the end user, by means of transformation processes which include printing the desired informative and / or decorative elements on the printable side of the support layer, then cutting them to the desired shape and dimensions. The protective release layer can be easily removed without modifying the adhesive layer which remains fixed on the support layer. After separation from its protective release layer, the label is applied to the article to be coated either manually or using labeling machines on automated packaging lines.
[0008] These multilayer systems can also be transformed into self-adhesive tapes by cutting and packaging in rolls of determined widths and lengths with cutting or pre-cutting of particular shapes useful for their final use, such as for example for the assembly of parts of variable size and variable shape, in the electronics industry, whether for applications in industry or by the general public.
[0009] Adhesive compositions crosslinkable by heating, based on polyurethane (or polyether) with hydrolyzable alkoxysilane termination, are already known, in particular from applications WO 09 / 106699 and EP2336208, the coating of which on a support and the heating leads, at the end of a chemical crosslinking reaction (hydrolysis and condensation) carried out in the presence of humidity, to the production of a self-adhesive support which has the required properties of adhesive power (or peel) and tack. This crosslinking reaction leads to the formation of an adhesive joint which has a three-dimensional polymer network structure comprising siloxane bonds and which ensures the fixing of the self-adhesive support on the substrate. Said self-adhesive support can thus be used for the manufacture of labels and / or self-adhesive tapes.
[0010] Self-adhesive labels or tapes can be used in im high temperatures, such as for example for protecting, masking, labeling or decorating parts in car engines or exhaust pipes, for protecting electronic or electrical components during manufacturing processes, for cable wrapping in cars, or for product assembly in the transport industry. In these types of applications, self-adhesive labels / tapes that are resistant to high temperatures are required. However, it is often difficult to achieve good thermal resistance while maintaining good adhesive properties.
[0011] There is therefore a need for new adhesive compositions which, after crosslinking, present a compromise between good adhesive properties (for example 180° peeling), and good resistance to aging, particularly under restrictive temperature and humidity conditions.
[0012] There is in particular a need for new adhesive compositions which, after crosslinking, have good resistance to high temperatures (for example greater than or equal to 200°C). DESCRIPTION OF THE INVENTION Composition
[0013] The present invention relates to a moisture-curable adhesive composition comprising:
[0014] - at least one silylated polymer (A);
[0015] - a tackifying resin (B);
[0016] - at least one compound (C) chosen from the group consisting of:
[0017] O compounds of formula (Fl) and their oligomeric / polymeric derivatives:
[0018] R0-O-[-Si(OR°)2-O-]t-R0 (Fl)
[0019] in which: - R° is independently chosen from alkyls and aryls, - t represents an integer ranging from 1 to 20, preferably from 1 to 7;
[0020] O compounds of formula (F2): (F2)
[0021] in which: - R'° is independently selected from alkyl groups comprising from 1 to 10 carbon atoms, - u is an integer ranging from 3 to 5000,
[0022] O aminopolysiloxane compounds; and
[0023] O of their mixtures;
[0024] said composition being characterized in that it has a glass transition temperature ranging from -25°C to 20°C.
[0025] The glass transition temperature (Tg) can be measured by dynamic mechanical analysis (DMA). A preferred method is in particular that implemented in the experimental part.
[0026] Preferably, the adhesive composition is such that it has a glass transition temperature ranging from -25°C to 20°C, preferably from -20°C to 15°C. Silylated polymer (A)
[0027] The silylated polymer (A) preferably comprises at least one hydrolyzable alkoxysilane group, and preferably at least two hydrolyzable alkoxysilane groups.
[0028] The silylated polymer (A) is preferably a polymer comprising at least one, preferably at least two hydrolyzable groups of formula (I), in particular terminal (aux):
[0029] -Si(R4)p(OR5)3 p (I)
[0030] in which: - R4 represents a linear or branched alkyl group comprising from 1 to 4 carbon atoms, with the possibility that when there are several R4 radicals, the latter are identical or different; - R5 represents a linear or branched alkyl group comprising from 1 to 4 atoms of carbon, with the possibility that when there are several R5 radicals, these are identical or different, with the possibility that two OR5 groups can be engaged in the same cycle; and - p is an integer equal to 0, 1 or 2, preferably equal to 0 or 1.
[0031] According to the invention, the silylated polymer may have a polyether main chain, a polyester main chain, a polyester-polyether-polyester main chain, a polyether-polyester-polyether main chain, a polyolefin main chain, a polycaprolactone main chain, a polyacrylate main chain, a polycarbonate main chain, a polyether-polycarbonate main chain, a polyester-polycarbonate main chain, a polyacetal main chain, a polyester-polyamide main chain, a polythioether main chain, a polyurethane main chain, a polyester-polyurethane main chain, a polyether-polyurethane main chain, a polyether-polyester-polyurethane main chain, a polyolefin-polyurethane main chain, a polyether-polyolefin-polyurethane main chain.
[0032] The silylated polymer may have a number average molecular weight ranging from 500 to 50,000 g / mol, preferably ranging from 700 to 40,000 g / mol.
[0033] The number-average molecular mass of the silylated polymers (A) can be measured by methods well known to those skilled in the art, for example by size exclusion chromatography using polystyrene-type standards.
[0034] According to one embodiment of the invention, the silylated polymer (A) corresponds to one of the following formulas (II), (III) or (IV): NH-R—SKR^OR^ (III) :0V)
[0035] in which: - R4, R5 and p have the same meaning as in formula (I) described above, - P represents a saturated or unsaturated, linear or branched polymeric radical optionally comprising one or more heteroatoms, such as oxygen, nitrogen, sulfur, silicon, and preferably having a number-average molar mass ranging from 100 g / mol to 50,000 g / mol, more particularly from 500 g / mol to 40,000 g / mol; - R1 represents a divalent hydrocarbon radical comprising from 5 to 15 carbon atoms which can be aromatic or aliphatic, - R3 represents a linear or branched divalent alkylene radical comprising from 1 to 6 carbon atoms, preferably from 1 to 3 carbon atoms, - X represents a divalent radical chosen from -NH-, -NR7- or -S-, - R7 represents a linear or branched alkyl group comprising from 1 to 20 carbon atoms and which may also comprise one or more heteroatoms, and - f is an integer ranging from 1 to 6, preferably ranging from 2 to 5, preferably from 2 to 4, more preferably ranging from 2 to 3.
[0036] Preferably, in formulas (II), (III) and / or (IV) above, P represents a polymeric radical chosen in a non-limiting manner from polyethers, polycarbonates, polyesters, polyolefins, polyacrylates, polyether polyurethanes, polyester polyurethanes, polyolefin polyurethanes, polyacrylate polyurethanes, polycarbonate polyurethanes, polyether / polyester block polyurethanes.
[0037] For example, document EP 2468783 describes silylated polymers of formula (II) in which P represents a polymer radical with polyurethane / polyester / polyether blocks.
[0038] According to one embodiment, the silylated polymers (A) are chosen from silylated polyurethanes, silylated polyethers, and mixtures thereof.
[0039] Preferably, the silylated polymer (A) corresponds to one of the formulas (II'), (III') or (IV'): (RSQK ^t\si-R—.WH-C—O—rZo—C—NH-R—NH-C—O —R^-O—C—NHtR—SifR4UOR\,. ' ” il T- il Z, Il ' p OOOO
[0040] (II') ^432 4 (R^O), JR VSf-R—O—R—O—R—SKR UORh r
[0041] (III) R—X— C— MH-R— MH-C — O — Rq-O—C—NH-R— NH-C—O— r4-O—C— HH-R—NH-û—X— S—SiiK >p(OR% „ ' ' Il II L hh J h II GGGGOO
[0042] (IV')
[0043] in the following: - R1, R3, R4, R5, X, R7 and p have the same meaning as in Formulas (II), (III) and (IV) described above, - R2 represents a saturated or unsaturated, linear or branched, divalent hydrocarbon radical optionally comprising one or more heteroatoms, such as oxygen, nitrogen, sulfur, silicon, and preferably having a mass molar in number ranging from 100 g / mol to 48,600 g / mol, more particularly from 300 g / mol to 38,600 g / mol, and - n is an integer greater than or equal to 0.
[0044] In the silylated polymers (A) of formulae (II'), (III') or (IV') defined above, when the radical R2 comprises one or more heteroatoms, said heteroatoms are not present at the end of the chain. In other words, the free valences of the divalent radical R2 linked to the oxygen atoms adjacent to the silylated polymer each come from a carbon atom. Thus, the main chain of the radical R2 is terminated by a carbon atom at each of the two ends, said carbon atom then having a free valence.
[0045] According to one embodiment, the silylated polymers (A) are obtained from polyols chosen from polyether polyols, polyester polyols, polycarbonate polyols, polyacrylate polyols, polysiloxane polyols and polyolefin polyols and mixtures thereof, and more preferably from diols chosen from polyether diols, polyester diols, polycarbonate diols, polyacrylate diols, polysiloxane diols, polyolefin diols and mixtures thereof. In the case of the polymers of formulae (II'), (III') or (IV') described above, such diols may be represented by the formula H0-R2-OH where R2 has the same meaning as in formulae (II'), (III') or (IV').
[0046] For example, among the radicals of type R2 which may be present in formulas (II'), (III') or (IV'), we may cite the following divalent radicals whose formulas below show the 2 free valences:
[0047] - derived from a polypropylene glycol:
[0048] - derivative of a polyester diol:
[0049] - derivative of a polybutadiene diol:
[0050] - derivative of a polyacrylate diol:
[0051]
[0052]
[0053]
[0054]
[0055]
[0056]
[0057]
[0058]
[0059]
[0060] - derived from a polysiloxane diol: In the above formulas, the meaning of the radicals and indices is as follows: - q represents an integer such that the number-average molecular mass of the radical R2 ranges from 100 g / mol to 48600 g / mol, preferably from 300 g / mol to 18600 g / mol, more preferably from 500 g / mol to 12600 g / mol, - r and s represent zero or a non-zero integer such that the number-average molecular mass of the radical R2 ranges from 100 g / mol to 48600 g / mol, preferably from 300 g / mol to 18600 g / mol, more preferably from 500 g / mol to 12600 g / mol, it being understood that the sum r+s is different from zero, - Q1 represents a linear or branched, saturated or unsaturated, aromatic or aliphatic divalent alkylene radical, preferably having from 1 to 18 carbon atoms, more preferably from 1 to 8 carbon atoms, - Q2 represents a linear or branched divalent alkylene radical preferably having from 2 to 36 carbon atoms, more preferably from 1 to 8 carbon atoms, - Q3, Q4, Q5, Q6, Q7 and Q8, represent, independently of one another, a hydrogen atom or an alkyl, alkenyl or aromatic radical, preferably having from 1 to 12 carbon atoms, preferably from 2 to 12 carbon atoms, more preferably from 2 to 8 carbon atoms. Preferably, the silylated polymer (A) is such that the radical R2 which appears in the formulae (II'), (III') and (IV') represents a polyether radical, preferably a poly(oxyalkylene) radical, and even more preferably a radical derived from a polypropylene glycol corresponding to the formula indicated above. According to one embodiment, R1 is chosen from one of the following divalent radicals whose formulas below show the 2 free valences: a) the divalent radical derived from isophorone diisocyanate (IPDI):
[0061] b) the divalent radical derived from dicyclohexylmethane diisocyanate (H12MDI)
[0062]
[0063] c) the divalent radical derived from toluene diisocyanate (TDI) O' A d) divalent radicals derived from the 4,4' and 2,4'- isomers of diphenylmethane diisocyanate (MDI)
[0064]
[0065]
[0066] e) the divalent radical derived from hexamethylene diisocyanate (HDI)-(CH2)e- f) the divalent radical derived from m-xylylene diisocyanate (m-XDI) 6.. The polymers (A) of formula (II) or (II') can be obtained according to a process described in documents EP 2336208 and WO 2009 / 106699. A person skilled in the art will be able to adapt the manufacturing process described in these two documents in the case of the use of different types of polyols. Among the polymers corresponding to formula (II), mention may be made of: - GENIOSIL® STP-E10 (available from WACKER): polyether comprising two dimethoxy groups (I) (n equal to 0, p equal to 1 and R4 and R5 represent a methyl group) with a number-average molar mass of 16,928 g / mol where R3 represents a methyl group; - GENIOSIL® STP-E30 (available from WACKER): polypropylene glycol with 2 alpha silane functions of methyl dimethoxy type with a number-average molar mass of 24000 g / mol; - SPUR+® 1050MM (available from MOMENTIVE): polyurethane comprising two groups (I) of the trimethoxy type (n different from 0, p equal to 0 and R5 represents a methyl group) having a molar mass number average of 16393 g / mol where R3 represents an n-propyl group; - SPUR+® Y-19116 (available from MOMENTIVE): polyurethane comprising two groups (I) of the trimethoxy type (n different from 0 and R5 represents a methyl group) having a number-average molar mass ranging from 15000 to 17000 g / mol g / mol where R3 represents an n-propyl group; - DESMOSEAL® S XP 2636 (available from BAYER): polyurethane comprising two groups (I) of the trimethoxy type (n different from 0, p equal to 0 and R5 represents a methyl group) having a number-average molar mass of 15038 g / mol where R3 represents an n-propylene group.
[0067] The polymers (A) of formula (III) or (III') can be obtained by hydrosilylation of polyether diallyl ether according to a process described for example in document EP 1829928.
[0068] Among the polymers corresponding to formula (III), we can cite:
[0069] - the MS SAX® 530 polymer (available from KANEKA) corresponding to a polyether comprising two groups (I) of trimethoxy type (p equal to 1 and R4 and R5 represent a methyl group) having a weight-average molar mass ranging from 14000 to 16000 g / mol;
[0070] - the MS SAX® 260 polymer (available from KANEKA) corresponding to a polyether comprising two groups (I) of dimethoxy type (p equal to 1, R4 and R5 represent a methyl group) having a weight-average molar mass of 16000 to 18000 g / mol where R3 represents an ethyl group;
[0071] - the MS S303H polymer (available from KANEKA) corresponding to a polyether comprising three groups (I) of dimethoxy type (p is equal to 1 and R4 represents a methyl group) having a weight-average molecular mass of approximately 22,000 Dalton.
[0072] The silylated polymers (A) of formula (IV) or (IV') can for example be obtained by reaction of polyol(s) with one or more diisocyanate(s) followed by a reaction with aminosilanes or mercaptosilanes. A process for preparing polymers of formula (IV) or (IV') is described in document EP 2 583 988. Those skilled in the art will be able to adapt the manufacturing process described in this document in the case of the use of different types of polyols.
[0073] According to a preferred embodiment of the invention, the adhesive composition comprises at least one silylated polymer (A) of formula (II) and / or (II') or at least one silylated polymer of formula (III) and / or (III').
[0074] According to a very particularly preferred embodiment of the invention, the polymer silylated is a silylated polymer of formula (II') in which R2 is a divalent radical derived from a polyether, preferably from a poly(oxyalkylene) diol, and even more particularly from a polypropylene glycol.
[0075] Preferably, the adhesive composition according to the invention comprises from 5% to 80% by weight of silylated polymer(s) (A), preferably from 15% to 70% by weight, and even more preferably from 20% to 60% by weight relative to the total weight of said composition. Tackifying resin (B)
[0076] The adhesive composition according to the invention also comprises at least one tackifying resin (B).
[0077] Said resin may be any resin compatible with the silylated polymer(s) (A).
[0078] The term "compatible tackifying resin" is intended to mean a tackifying resin which, when mixed in proportions 50% / 50% with the silylated polymer(s) (A), gives a substantially homogeneous mixture.
[0079] The softening temperature (or point) is determined in accordance with the standardized ASTM E28 test, the principle of which is as follows: a brass ring with a diameter of approximately 2 cm is filled with the resin to be tested in the molten state. After cooling to room temperature, the ring and the solid resin are placed horizontally in a glycerin or other thermostatically controlled bath, the temperature of which can vary by 5°C per minute. A steel ball with a diameter of approximately 9.5 mm is centered on the solid resin disc. The softening temperature is - during the phase of heating the bath at a rate of 5°C per minute - the temperature at which the fine resin disc, 25.4 mm high, is under the weight of the ball.
[0080] The tackifying resin (B) preferably has a softening temperature ranging from 60°C to 115°C, more preferably from 80°C to 110°C.
[0081] The resins (B) are advantageously chosen from:
[0082] - (i) terpene resins;
[0083] - (ii) resins obtained by a process comprising polymerization alpha-methyl styrene, said process also including reaction with phenols;
[0084] - (iii) rosins of natural or modified origin, (such as for example rosin extracted from pine gum, wood rosin extracted from the roots of the tree and their derivatives hydrogenated, dimerized, polymerized or esterified by monoalcohols or polyols, such as glycerol or pentaerythritol);
[0085] - (iv) aliphatic hydrocarbon resins, optionally partially or completely fully hydrogenated,
[0086] - (v) cycloaliphatic hydrocarbon resins, optionally partially or fully hydrogenated;
[0087] - (vi) modified aliphatic or cycloaliphatic hydrocarbon resins aromatic, possibly partially or totally hydrogenated,
[0088] - (vii) acrylic resins having a viscosity at 100°C of less than 100 Pa.s; and
[0089] - (viii) mixtures of these resins.
[0090] Terpene resins include, in particular, resins synthesized by (co)-polymerization of one or more terpene monomers such as, for example, α-pinene, β-pinene, D-Lhnonene; resins synthesized by copolymerization of one or more terpene monomers with one or more non-terpene monomers, for example chosen from styrene, methylstyrene, isoprene, etc.; terpene-phenolic resins; and their partially or totally hydrogenated derivatives.
[0091] Resins synthesized by (co)polymerization of one or more terpene monomers are known under the name polyterpenes.
[0092] Terpene-phenolic resins, (or also called terpene-phenols) are typically obtained by polymerization of terpene hydrocarbons and phenols, in the presence of a Friedel-Crafts catalyst.
[0093] Among the terpene resins, terpene-phenolic resins are preferred.
[0094] Among the terpene resins, we can notably cite Dercolyte® M105 available from the company “Résiniques et Terpéniques or DRT” (which is a polyterpene resin having a softening temperature of 105°C), Dertophene ® T105 marketed by DRT (which is a terpene-phenolic resin having a softening temperature of 105°C), Dertophene® H150 available from the same company with a molar mass Mn equal to approximately 630 D, Sylvalite 1105 marketed by Kraton (which is a terpene-phenolic resin having a softening temperature of 105°C), PICCO® AR-85 available from the company EASTMAN (having a softening point of 85°C), “PICCO® AR-100” also available from the company EASTMAN (having a softening point of 100°C).
[0095] Among the resins of type (ii), we find in particular Cleartack® W100 available from the company Cray Valley, which is obtained by polymerization of alpha-methyl styrene without the action of phenols, with a number-average molar mass of 900 Da; Sylvarez® 510 which is also available from the company Arizona Chemical with a molar mass Mn of approximately 1740 Da, the process for obtaining which also includes the addition of phenols.
[0096] Among the resins of type (iii), we can for example cite Sylvalite® RE 100 which is an ester of rosin and pentaerethritol available from the company Arizona Chemical and with a molar mass Mn of approximately 1700 Da.
[0097] Aliphatic hydrocarbon resins, possibly partially or totally Hydrogenated resins are well known to those skilled in the art. These are resins resulting from the polymerization of mixtures of unsaturated aliphatic hydrocarbons having, for example, 5 carbon atoms (which may, for example, be derived from petroleum or other fractions), followed by a possible hydrogenation step (total or partial).
[0098] Partially or totally hydrogenated cycloaliphatic hydrocarbon resins are well known to those skilled in the art. These are resins resulting from the polymerization of mixtures of unsaturated cycloaliphatic hydrocarbons having, for example, 10 carbon atoms (which may, for example, be derived from petroleum or other fractions), followed by a possible hydrogenation step (total or partial). They can in particular be obtained from dicyclopentadiene and their derivatives (methyldicyclopentadiene, dimethyldicyclopentadiene, etc.). Among the cycloaliphatic hydrocarbon resins, DCPD (dicyclopentadiene) resins are particularly preferred.
[0099] The aromatic modified aliphatic or cycloaliphatic hydrocarbon resins can be derived from the copolymerization of aliphatic (for example C5) or cycloaliphatic olefins, and aromatic (for example C9) olefins, followed by a possible hydrogenation step (total or partial), the content of aliphatic or cycloaliphatic olefins being in the majority compared to the aromatic olefins.
[0100] Examples include Eastotac® H100W (hydrogenated C5 resin) from Eastman having a softening point of 100°C, Escorez® 5400 resin from Exxon Chemicals (hydrogenated DCPD resin) having a softening point of 100°C, and Sukorez® SU 100 (hydrogenated DCPD resin) from Kolon having a softening point of 105°C.
[0101] Preferably, the tackifying resin (B) is chosen from terpene resins, and even more preferably from terpene-phenolic resins.
[0102] Preferably, the adhesive composition according to the invention comprises from 15% to 90% by weight of tackifying resin(s) (B), preferably from 30% to 80% by weight, and even more preferably from 40% to 70% by weight relative to the total weight of said composition. Compound (C)
[0103] Compound (C) is chosen from the group consisting of:
[0104] O compounds of formula (Fl) and their oligomeric / polymeric derivatives:
[0105] R0-O-[-Si(OR°)2-O-]tR° (Fl)
[0106] in which: - R° is independently chosen from alkyls and aryls, - t represents an integer ranging from 1 to 20, preferably from 1 to 7;
[0107] O compounds of formula (F2):
[0108] in which: - R'° is independently selected from alkyl groups comprising from 1 to 10 carbon atoms, - u is an integer ranging from 3 to 5000,
[0109] O aminopolysiloxane compounds; and
[0110] O of their mixtures. Compounds of formula (Fl) and their derivatives
[0111] In the above-mentioned formula (Fl), the R° groups may be the same or different. This is also true for different repeating units t, R° may be the same or different.
[0112] Oligomeric / polymeric derivatives of compounds of formula (F1) can typically be obtained by partial hydrolysis and partial condensation of compounds of formula (F1). This can be done by adding water and catalytic amounts of acid (such as, for example, HCl). Some hydrolyzed -OR groups then release water and the intermediate silanols react by condensation to form Si-O-Si bonds and water.
[0113] Preferably, the compounds of formula (F1), and their oligomeric / polymeric derivatives are those in which:
[0114] - R° is chosen from ethyl, n-propyl, butyl, or isopropyl; and / or
[0115] -1 represents an integer ranging from 1 to 20.
[0116] Even more preferably, the compounds of formula (F1), and their oligomeric / polymeric derivatives, are those in which:
[0117] - R° is ethyl; and / or
[0118] -1 is an integer ranging from 2 to 7.
[0119] The compounds (C) may be chosen from tetra-ethoxyorthosilicates, tetra-propoxyorthosilicates, tetra-isopropoxyorthosilicates, tetra-butoxyorthosilicates, their oligomeric / polymeric derivatives, and their mixtures.
[0120] Preferably, the compounds (C) are chosen from tetraethoxyorthosilicate, their oligomeric / polymeric derivatives, and their mixtures.
[0121] Such compounds are, for example, marketed by Wacker under the name Wacker® silicate TES 40 WN (partially oligomerized tetraethoxyorthosilicate), or by Evonik under the name Dynasylan® 40 marketed (partially oligomerized tetraethoxyorthosilicate), or TES28 marketed by Wacker (CAS 78-10-4, R = ethyl, and n = 1). Compounds of formula (F2)
[0122] In the above-mentioned formula (F2), the R'° groups may be the same or different. This is also true for different repeating units u, R'° may be the same or different.
[0123] The compound of formula (F2) may have a number-average molecular mass ranging from 100 to 300,000 g / mol, preferably from 200 to 100,000 g / mol, and even more preferably from 500 to 50,000 g / mol.
[0124] The number-average molecular mass of the compounds of formula (F2) can be measured by methods well known to those skilled in the art, for example by size exclusion chromatography using standards, for example of the polystyrene type.
[0125] The compounds of formula (F2) are preferably those in which: - R'° is independently selected from alkyl groups comprising from 1 to 2 carbon atoms; - u is an integer ranging from 5 to 3000.
[0126] The compounds of formula (F2) are notably marketed by the company CHT under the name HANSA SFA 92135 or HANSA SFA 92013. Aminopolysiloxanes
[0127] Aminopolysiloxanes are polysiloxanes functionalized with at least one amino group. The term “amino group” includes a primary amine, secondary amine or tertiary amine functional group.
[0128] The aminopolysiloxanes preferably have the following formula (F3): oc'— 1 A? 1 JJ 1 i ce: - - ÛJ 1 -LD -ï O 1 -St—O- - -Si—O- -Si— R 1 & jfj -ce! _____________ / i -^1 S R-( (F3)
[0129] in which: - Ra, Rb, Rc, Rd, Re, Rf, R", Rh, R', or R1, represent, independently of one another, a linear or branched alkyl group, an aryl group, a cycloaliphatic group, an alkoxy group, a group -NRpRq with Rp and R^ representing, independently of one another, a hydrogen atom, an optionally substituted alkyl radical, an aryl radical; - x represents an integer ranging from 1 to 100; - y represents an integer ranging from 1 to 1,000.
[0130] characterized in that at least one of the groups Ra, Rb, Rc, Rd, Re, Rf, R®, Rh, R', or R1, represents a group -NRpRq with Rp and R^ representing, independently of one another, a hydrogen atom, an optionally substituted alkyl radical, an aryl radical.
[0131] The aminopolysiloxanes of formula (F3) are preferably those in which: - Ra, Rb, Rc, Rd, Re, Rf, R", Rh, R', or R1, independently of each other represent a linear or branched alkyl group having from 1 to 6 carbon atoms, preferably from one to two carbon atoms, an alkoxy group, a group -NRpRq with Rp and R^ representing, independently of each other, a hydrogen atom, an optionally substituted alkyl radical, an aryl radical; - x represents an integer ranging from 1 to 100; - y represents an integer ranging from 1 to 1000.
[0132] Among the aminopolysiloxanes, mention may be made, for example, of (2-aminoethyl)methylpolysiloxane, (3-aminopropyl)methylpolysiloxane, (2-aminoethyl 1-3 - aminopropyl)methylpoly siloxane, (3-2-aminoethylamino)propyl)methylsiloxane, (6-aminohexyl)methylpolysiloxane, and mixtures thereof.
[0133] Among the compounds of formula (F3), we can for example cite HANSA SFA 8030 or HANSA SFA 8018 marketed by the company CHT.
[0134] Preferably, compound (C) is chosen from the compounds of formula (F1) mentioned above and their oligomeric / polymeric derivatives.
[0135] Preferably, the compounds (C) are chosen from tetraethoxyorthosilicates, their oligomeric / polymeric derivatives, and their mixtures.
[0136] Preferably, the adhesive composition according to the invention comprises from 1% to 50% by weight of compounds (C), preferably from 4% to 40% by weight, and even more preferably from 5% to 20% by weight relative to the total weight of said composition. Crosslinking catalyst (D)
[0137] Preferably, the adhesive composition according to the invention also comprises at least one crosslinking catalyst (D).
[0138] The latter may be any catalyst known to those skilled in the art for the condensation of silanol.
[0139] The crosslinking catalyst (D) can be chosen from the group consisting of:
[0140] (Dl) organometallic compounds,
[0141] (D2) amines, and
[0142] (D3) acids and their derivatives,
[0143] as well as their mixtures.
[0144] It may also be a mixture of catalysts belonging to the same group (D1), (D2) or (D3) (for example a mixture of several amines), or a mixture of catalysts belonging to at least 2 different groups chosen from the groups (D1), (D2) and (D3) (for example a mixture of an amine and an organometallic compound).
[0145] In the context of the invention, the term "organometallic compounds" means compounds comprising an organic radical and at least one metal. In the context of the invention, the term "organic radical" means a radical comprising at least one carbon atom.
[0146] (D1) Organometallic compounds:
[0147] Organometallic compounds may include organometallic compounds (compounds comprising at least one metal-carbon covalent bond), metal alcoholates, metal carboxylates, and metal coordination complexes with organic ligand(s).
[0148] Examples of organic ligands include acetylacetonate and oximes.
[0149] The metal atom of the organometallic compounds may be any metal atom known to those skilled in the art, and may in particular be chosen from tin, aluminum, zinc, cobalt, iron, nickel, bismuth, titanium, or zirconium. The organometallic compounds may also comprise several metal atoms.
[0150] Compounds comprising at least one metal-carbon covalent bond:
[0151] The compounds comprising at least one metal-carbon covalent bond (organometallic compounds) may be carboxylates of organometallic compounds, selected from the group consisting of dibutyl tin dilaurate (DBTL), dibutyl tin diacetate, dibutyl tin diethylhexanoate, dioctyl tin dineodecanoate (for example available under the name TIB KAT® 223 from the company TIB CHEMICALS), dibutyl tin dioleate, dibutyl tin benzylmaleate, diphenyl tin diacetate, and mixtures thereof.
[0152] The metal alcoholates may be selected from the group consisting of titanium tetrabutanolate, titanium tetraisopropylate, zirconium tetrabutanolate, zirconium tetraisopropylate, and mixtures thereof.
[0153] The metal carboxylates may be selected from the group consisting of zinc 2-ethylcaproate, zinc diacetate, zinc dineodecanoate, zinc diun-decenoate, zinc dimethacrylate, cobalt acetylacetonate, cobalt diacetate, iron acetylacetonate, iron diacetate, nickel acetylacetonate, nickel diacetate, bismuth acetate, bismuth trioctanoate, bismuth dineodecanoate, zinc bismuth dineodecanoate, and their mixtures.
[0154] The metal coordination complexes with one or more organic ligands may be chosen from the group consisting of zinc acetylacetonate, titanium acetylacetonate (for example commercially available under the name TYZOR ® AA75 from the company DORF KETAL), titanium tetraacetylacetonate, aluminum trisacetylacetonate, aluminum chelates such as for example mono-acetylacetonate bis-(ethylacetoacetate) (for example commercially available under the name K-KAT ® 5218 from the company KING INDUSTRIES), zirconium tetraacetylacetonate, diiso-propoxybis(ethylacetonato)titanium, and mixtures thereof.
[0155] (D2) Amines:
[0156] The amines may be primary amines, secondary amines or tertiary amines.
[0157] Preferably, the amines are selected from the group consisting of triethylamine, tributylamine, tetramethylguanidine, 1,8-diazabicyclo[5.4.0]-7-undecene, 1,4-diazabicyclo[2.2.2]octane, 1,5-diazabicyclo[4.3.0]non-5-ene, N,N-bis(N,N-dimethyl-2-aminoethyl)methylamine, N,N-dimethylcyclohexaylamine, N,N-dimethylphenylamine, N-ethylmorpholine, and mixtures thereof.
[0158] (D3) Acid catalysts and their derivatives:
[0159] The acid catalysts may be chosen from inorganic acid catalysts, organic acid catalysts, and mixtures thereof.
[0160] Among the inorganic acid catalysts, we can for example cite phosphoric or orthophosphoric acid, phosphorous acid, hypophosphorous acid, or sulfuric acid.
[0161] The organic acid catalysts may be chosen from sulfonic acids, carboxylic acids, acid organophosphates, acid organophosphonates, phosphonic acids, and mixtures thereof.
[0162] Preferably, the organic and inorganic acid catalysts have a pKa less than or equal to 6, preferably less than or equal to 4, advantageously less than or equal to 2, advantageously less than or equal to 0.
[0163] The sulfonic acids may be aliphatic or aromatic, optionally substituted (for example substituted by at least one substituent chosen from halogens (such as fluorine), hydroxyls, alkyls, amines, and mixtures thereof), and may be mono- or disulfonic.
[0164] The sulfonic acids may be chosen from N-alkylaminoalkylsulfonic acids and N,N-dialkylaminoalkylsulfonic acids (zwitterions), such as for example 2-(N-Morpholino)ethanesulfonic acid, 3-(N-morpholino)propanesulfonic acid, 4-[N-morpholino]butanesulfonic acid, 1,4-piperazinediethanesulfonic acid, N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid, 2-(N-morpholino)ethanesulfonic acid, N -Morpholinomethanesulfonic acid, N-(2-hydroxyethyl)piperazine-N'-methanesulfonic acid, piperazine-N,N'-bis(methanesulfonic acid), cyclohexylaminomethanesulfonic acid, N-[tris(hydroxymethyl)methyl]-aminomethanesulfonic acid, N,N-bis(2-hydroxyethyl)aminomethanesulfonic acid; para-toluenesulfonic acid; benzenesulfonic acid; methanesulfonic acid; dodecylbenzenesulfonic acid; dodecylbenzene disulfonic acid; dinonylnaphthalene disulfonic acid; dinonylnaphthalene sulfonic acid; trifluoromethylsulfonic acid; and mixtures thereof.
[0165] In particular, the sulfonic acids are chosen from para-toluene sulfonic acid, benzene sulfonic acid, methanesulfonic acid, dodecylbenzene sulfonic acid, dodecylbenzene disulfonic acid, dinonylnaphthalene disulfonic acid, dinonylnaphthalene sulfonic acid, trifluoromethylsulfonic acid, and mixtures thereof.
[0166] Among the carboxylic acid catalysts, there may be mentioned, for example, malonic acid, succinic acid, maleic acid, oxalic acid, acetic acid, lactic acid, benzoic acid, citric acid, glycolic acid, and mixtures thereof.
[0167] In the context of the invention, and unless otherwise stated, the term "acid organophosphate" means an ester of phosphoric acid comprising at least one -OH radical. For example, methyl phosphate is an acid organophosphate comprising two -OH radicals and has the following structure: O II HO —F —O—CH 3 OH
[0168] In particular, acid organophosphates have the following formula:
[0169] (RO)g-(P=O)-(OH)h
[0170] in which: - R is an organic radical, in particular a radical chosen from linear or branched C1-C22 alkyls, cycloalkyls, aryls, and mixtures thereof (said alkyl, cycloalkyl and aryl groups being optionally substituted); and - g and h are integers, with g + h = 3 and h = 1 or 2.
[0171] The acid organophosphates may, for example, be chosen from the group consisting of C1-C22 mono- or dialkyl acid phosphates and mixtures thereof, such as, for example, butyl phosphate, dibutyl phosphate, di-(2-ethylhexyl) phosphate, 2-ethylhexyl phosphate and mixtures thereof; mono- or diaryl phosphates and mixtures thereof, such as, for example, monophenyl phosphate, diphenyl phosphate and mixtures thereof; alkyl-phenyl phosphates; and mixtures thereof.
[0172] In the context of the invention, and unless otherwise stated, the term “organophosphonate acid” means a phosphorus compound having the following general formula:
[0173] R'-(P=O)-(OH)(OR”)
[0174] in which R' and R” are organic radicals, preferably chosen independently of one another, from linear or branched C1-C22 alkyls, cycloalkyls, aryls, and mixtures thereof (said alkyl, cycloalkyl and aryl groups being optionally substituted).
[0175] Among the acid organophosphonates, we can for example cite the C1-C22 monoalkyl acid phosphonates.
[0176] In the context of the invention, and unless otherwise stated, the term "phosphonic acid" means a phosphorus compound having the following general formula:
[0177] R'”-(P=O)-(OH)2
[0178] in which R”' is an organic radical, preferably chosen from linear or branched C1-C22 alkyls, cycloalkyls, aryls, and mixtures thereof (said alkyl, cycloalkyl and aryl groups being optionally substituted).
[0179] Among the phosphonic acids, mention may be made, for example, of N-alkylaminoalkylphosphonic acids (zwitterions), N,N-dialkylaminoalkylphosphonic acids (zwitterions), C1-C20 alkylphosphonic acids such as, for example, methylphosphonic acid, ethylphosphonic acid, propylphosphonic acid, butylphosphonic acid, t-butylphosphonic acid, isobutylphosphonic acid, hexylphosphonic acid, ethyl-2-hexylphosphonic acid and higher linear or branched homologues, benzylphosphonic acid, phenylphosphonic acid, toluylphosphonic acid, xylylphosphonic acid.
[0180] Examples of organic acid catalysts that may be mentioned include NACURE ® 155 (dinonylnaphthalene disulfonic acid, 55% active ingredient in isobutanol) marketed by KING INDUSTRIES, NACURE ® 1051 (dinonylnaphthalene sulfonic acid, 50% active ingredient in 2-butoxyethanol) marketed by KING INDUSTRIES, NACURE ® 5076 (dodecylbenzene sulfonic acid, 70% active ingredient in isopropanol) marketed by KING INDUSTRIES, K-CURE ® 1040 (para-toluene sulfonic acid, 40% active ingredient in isopropanol) marketed by KING INDUSTRIES, NACURE ® 4000 (mixture of mono and dialkyl acid phosphates, 100% active ingredient) marketed by KING INDUSTRIES.
[0181] The acid derivatives according to the invention may be acid anhydrides, acid esters, acid ammonium salts, the acid being as described above.
[0182] The acid derivatives are in particular so-called "blocked" or "latent" acids which advantageously allow the acid to be released by thermal activation (for example at a temperature ranging from 70°C to 170°C, preferably at a temperature ranging from 90°C to 120°C) or by hydrolysis, or by photoactivation, preferably by thermal activation. The blocked acid advantageously allows the acid which is the entity having the catalytic activity to be released. For example, the ammonium salt formed between amino methyl propanol and para-toluene sulfonic acid is a blocked acid (acid derivative) which, upon thermal activation, releases para-toluene sulfonic acid.
[0183] The acid derivatives may be prepared by any means known to those skilled in the art from the corresponding acid, for example by using typical acid / base reactions. For example, the method for making an ester typically involves the condensation of an acidic compound with a compound comprising a hydroxyl group such as for example an alcohol, or with an oxirane compound. The ammonium salts may be prepared from any of the above-mentioned acids, with ammonia or with a primary, secondary or tertiary amine. The amines may optionally comprise at least one functional group such as a hydroxy group (alkanolamines), a C1-C4 alkyl group.Ammonium salts (zwitterions) can also be prepared by changing the pH of a solution containing, for example, N-alkylaminoalkylphosphonic acids, N,N-dialkylaminoalkylphosphonic acids, N-alkylaminoalkylsulfonic acids or N,N-dialkylaminoalkylsulfonic acids.
[0184] Preferably, the catalyst is an ammonium salt of a sulfonic acid (the sulfonic acid being as described above), an ammonium salt of a phosphonic acid (the phosphonic acid being as described above), an ammonium salt of an acidic organophosphonate (the acidic organophosphonate being as described above), or an ammonium salt of an acidic organophosphate (the acidic organophosphate being as described above).
[0185] As amines for the preparation of ammonium salts, mention may be made, for example, of 2-amino-2-methyl-1-propanol, triethylamine, aniline, pyridine, dimethylaminoethanol, alkylpyridines, diisopropanolamine, dimethylethanolamine, triethanolamine, oxazolidines, bicyclic oxazolidines, amidines, diaza-bicyclooctanes, guanidines, N-alkyl morpholine, aminopyridine, ami-noalkylpyridines, aminopyrrolidines, indazole, imidazole, pyrazole, pyrazine, pyrimidine, purine, imidazoline, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholines, and mixtures thereof. Preferably, the amines are tertiary amines.
[0186] Examples of acid derivatives that may be mentioned include NACURE ® 3327 or NACURE ® 3525 (amine-blocked dinonylnaphthalene disulfonic acid, 25% active ingredient in isopropanol and isobutanol) marketed by KING INDUSTRIES, NACURE ® 1557 or NACURE ® 1953 (amine-blocked dinonylnaphthalene sulfonic acid, 25% active ingredient in a butanol and 2-butoxyethanol mixture) marketed by KING INDUSTRIES, NACURE ® 5225 or NACURE ® 5528 or NACURE ® 5925 (amine-blocked dodecylbenzene sulfonic acid, 25% active ingredient in isopropanol) marketed by KING INDUSTRIES, NACURE ® 2107 or NACURE ® 2500 (amine-blocked para-toluene sulfonic acid, 25% or 26% active ingredient in isopropanol) marketed by KING INDUSTRIES, NACURE ® 2501 or NACURE ® 2530 (amine-blocked para-toluene sulfonic acid, 25% active ingredient in isopropanol and methanol) marketed by KING INDUSTRIES,NACURE ® 4167 (dialkyl phosphate blocked by an organic amine, at 25% active ingredient in a mixture of isopropanol and isobutanol) marketed by KING INDUSTRIES, NACURE ® 4575 (acid phosphate blocked by an amine, at 25% active ingredient in a mixture of methanol and butanol) marketed by KING INDUSTRIES.
[0187] Preferably, the catalyst is chosen from the group consisting of organometallic compounds, and more preferably from the group consisting of metal alcoholates.
[0188] The composition according to the invention may comprise from 0.001% to 5% by weight, preferably from 0.01% to 3% by weight, and even more preferably from 0.05% to 1% by weight of catalyst (D) relative to the total weight of said composition. Other additives
[0189] The moisture-crosslinkable adhesive composition according to the invention may also comprise one or more additives chosen from the group consisting of moisture absorbers, plasticizers, antioxidants, pigments, dyes, adhesion promoters, UV stabilizers, solvents, flame retardant additives or even fillers.
[0190] The moisture absorber (or desiccant) may for example be chosen from hydrolyzable, non-polymeric alkoxysilane derivatives of lower molecular mass at 500 g / mol, preferably selected from trimethoxysilane and trimethoxysilane derivatives. Such an agent can typically extend the shelf life of the composition during storage and transport prior to use. Examples include gamma-methacryloxypropyltrimethoxysilane (e.g. available under the trade name SILQUEST ® A-174 from MOMENTIVE), methacryloxymethyltrimethoxysilane (e.g. available under the name GENIOSIL ® XL33 from WACKER), vinyltrimethoxysilane, risooctyltrimethoxysilane, or phenyltrimethoxysilane.
[0191] The moisture absorber content is preferably less than or equal to 3% by weight, more preferably less than or equal to 2% by weight relative to the total weight of composition A. When it is present, the moisture absorber may for example represent from 0.1% to 3% by weight or from 1% to 2% by weight relative to the total weight of the composition according to the invention.
[0192] The composition according to the invention may also comprise a plasticizing agent.
[0193] As an example of a plasticizing agent that can be used, any plasticizing agent usually used in the field of adhesives can be used, such as, for example, phthalates, benzoates, trimethylolpropane esters, trimethylolethane esters, trimethylolmethane esters, glycerol esters, pentaerythritol esters, naphthenic mineral oils, adipates, cyclohexyldicarboxylates, paraffinic oils, natural oils (optionally epoxidized), polypropylenes, polybutylenes, hydrogenated polyisoprenes, and mixtures thereof.
[0194] Among the phthalates, we can for example cite diisononyl phthalate, di-isobutyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, diisooctyl phthalate, diiso-dodecyl phthalate, dibenzyl phthalate or butylbenzyl phthalate.
[0195] Among the benzoates, we can for example cite: neopentyl glycol dibenzoate (for example available under the name UNIPLEX ® 512 from LANXESS), dipropylene glycol dibenzoate (for example available under the name BENZOFLEX ® 9-88SG from EASTMAN), a mixture of diethylene glycol dibenzoate and dipropylene glycol dibenzoate (for example available under the name K-FLEX ® 850 S from KALAMA CHEMICAL), or a mixture of diethylene glycol dibenzoate, dipropylene glycol dibenzoate and triethylene glycol dibenzoate (for example available under the name BENZOFLEX ® 2088 from EASTMAN).
[0196] Among the pentaerythritol esters, we can for example cite pentaerythritol tetravalerate (for example available under the name PEVALEN™ from the company PESTORP).
[0197] Among the cyclohexanedicarboxylates, we can for example cite diisononyl 1,2-cyclohexanedicarboxylate (for example available under the name HEXAMOLL DINCH ® from BASF).
[0198] The total content of plasticizer(s) in the composition according to the invention may range from 0% to 30% by weight, preferably from 0% to 30% by weight, or even for example from 0% to 15% by weight relative to the total weight of said composition. Preferably, the composition does not comprise a plasticizer.
[0199] The composition according to the invention may also comprise an antioxidant (also designated by the term UV stabilizing agent).
[0200] Antioxidants are compounds that may be introduced to protect the composition from degradation resulting from a reaction with oxygen that is likely to form by the action of heat or light. These compounds may include primary antioxidants that scavenge free radicals. Primary antioxidants may be used alone or in combination with other secondary antioxidants or UV stabilizers.
[0201] Examples include IRGANOX ® 1010, IRGANOX ® B561, IRGANOX ® 245, IRGANOX ® 1076, IRGAFOS ® 168 marketed by BASF.
[0202] An amount of antioxidant ranging from 0.1% to 3%, preferably from 1% to 3% by weight, based on the total weight of the composition according to the invention is generally used.
[0203] The solvents are preferably non-reactive solvents.
[0204] Among the solvents, we can for example cite polyols, alcohols, esters, ketones, and their mixtures.
[0205] The polyols may be chosen from diols, triols, and mixtures thereof. Preferably, they are polyester polyols, such as, for example, those described above.
[0206] Preferably, the composition according to the invention comprises a carbonated filler content of less than or equal to 15% by weight, more preferably less than or equal to 10% by weight, and even more preferably less than or equal to 5% by weight, relative to the total weight of said composition.
[0207] More preferably, the composition comprises less than 2% by weight of carbonated filler relative to the total weight of said composition, and in particular it does not comprise carbonated filler.
[0208] The composition according to the invention is advantageously a pressure-sensitive self-adhesive (PSA) composition.
[0209] The adhesive composition according to the invention advantageously leads, after crosslinking, to good adhesive properties at 23°C initially, but also good resistance to aging, in particular under restrictive temperature and humidity conditions.
[0210] The composition according to the invention advantageously has high resistance to wet poultice.
[0211] The adhesive composition according to the invention preferably has, after crosslinking, an adhesive power at 180° (peel at 180°) at 23°C greater than or equal to 0.4N / cm, determined according to the FINAT method No. 1 of 2001, preferably with a PET support.
[0212] The adhesive composition according to the invention may be in the form of a single-component adhesive composition or a multi-component adhesive composition, preferably two-component.
[0213] I, Single-component adhesive composition:
[0214] According to a first embodiment, the adhesive composition according to the invention is in the form of a single-component composition.
[0215] According to this embodiment, said single-component composition preferably comprises:
[0216] - from 5% to 80% by weight, preferably from 15% to 70% by weight, preferentially from 20% to 60% by weight of at least one silylated polymer (A);
[0217] - from 15% to 90% by weight, preferably from 30% to 80%, preferentially from 40% to 70% by weight of at least one tackifying resin (B);
[0218] - from 1 to 50% by weight, preferably from 4% to 40% by weight, preferentially from 5% to 20% by weight of at least one compound (C); and
[0219] - from 0% to 10%, preferably from 0.001% to 5%, preferentially from 0.01% to 3% in weight of crosslinking catalyst (D);
[0220] these percentages by weight being indicated on the basis of the total weight of single-component composition.
[0221] The single-component composition can be prepared by a process which comprises:
[0222] - a mixing step protected from air and moisture, preferably under at inert mosphere, of the polymer(s) (A) with the tackifying resin(s) (B), and of the compound(s) (C), at a temperature between 50 and 180°C, preferably between 100 and 160°C, then
[0223] - a step of cooling said mixture to a temperature ranging from 50 to 130°C, and advantageously from about 70°C to 90°C, then
[0224] - a step of incorporating into said mixture a possible reticulation catalyst culation (D) and, where applicable, other optional additives.
[0225] II, Multi-component adhesive composition:
[0226] According to a second embodiment, the adhesive composition according to the invention is in the form of a multi-component composition comprising:
[0227] - a composition U (as the 1st component) comprising:
[0228] - the silylated polymer(s) (A) as defined previously; and
[0229] - the tackifying resin(s) (B) as defined previously;
[0230] - optionally the compound(s) (C) as defined previously, and
[0231] - a composition V (as 2nd component) comprising:
[0232] - the compound(s) (C) as defined previously;
[0233] the optional catalyst (D) being included in composition V or in a composition W (3rd component).
[0234] The different components of said multi-component adhesive composition are intended to be mixed at the time of carrying out the crosslinking reaction, in accordance with the method for manufacturing a self-adhesive support described below.
[0235] The multi-component adhesive composition may comprise one or more additional compositions in addition to compositions U and V, said additional composition(s) being able to comprise any type of compound(s). For example, the multi-component adhesive composition may comprise an additional composition W comprising water. The water may be in liquid or gaseous form, or encapsulated, or absorbed, or contained in the chemical structure of a component. The water may be derived from one or more components which may make it free and available later.
[0236] The compositions U and V included in said adhesive composition (before mixing) are advantageously stable to storage, temperature and / or humidity. The greater stability over time advantageously allows for longer storage and handling with a lower risk of reaction, degradation or crosslinking of the compositions U and V, between their production and their hot application.
[0237] The multi-component adhesive composition according to the invention advantageously allows the formation of a uniform adhesive layer which does not present any problem of uncontrolled and inhomogeneous formation of grains or gels, and / or advantageously allows homogeneous crosslinking over the entire support layer.
[0238] According to an even more preferred embodiment, the multi-component adhesive composition according to the invention is a two-component adhesive composition consisting of the aforementioned compositions U and V. Kit
[0239] The present invention also relates to a kit comprising at least the aforementioned composition U and composition V in two separate compartments. The compartments may for example be drums, cartridges, bags. When the multi-component composition comprises other compositions (such as for example a composition W), these are contained in other compartments of the kit. Self-adhesive article
[0240] The present invention also relates to a self-adhesive article comprising a support layer coated with a self-adhesive layer, characterized in that said self-adhesive layer consists of the adhesive composition according to the invention in the crosslinked state.
[0241] For the purposes of the present invention, the term "self-adhesive article" includes any article that can be adhered to a surface solely by the action of pressure with the hand or equipment, without the use of additional glues or adhesives.
[0242] The self-adhesive article is a pressure-sensitive self-adhesive article.
[0243] The support layer coated with a self-adhesive layer is also referred to as "self-adhesive support".
[0244] These articles are intended in particular to be applied to a surface to be bonded in order to bring together, maintain, fix, or simply immobilize, expose shapes, logos, images or information. These articles can be used in many fields, such as the medical field, clothing, packaging, automotive (for example for the installation of logos, lettering, interior soundproofing, interior trim, bonding in the passenger compartment) or construction (for example for sound and thermal insulation, window assembly). They can be shaped according to their final application, for example in the form of tapes, such as tapes for industrial use, DIY tapes or for use on construction sites, single or double-sided tapes, or in the form of labels, bandages, dressings, patches or graphic films.
[0245] According to one embodiment, the self-adhesive article is a self-adhesive multi-layer system, and in particular a self-adhesive label or tape, which may be single- or double-sided.
[0246] The material that can be used for the support layer can, for example, be any type of rigid or flexible support. Examples include supports such as foams, felts, non-woven supports, plastics, membranes, papers or a film of a polymer material with one or more layers, in particular a non-stick protective paper or plastic film.
[0247] The support layer is made of a material chosen, for example, from polyolefins, such as polyethylene, including high-density polyethylene, low-density polyethylene, linear low-density polyethylene and linear ultra-low-density polyethylene, polypropylene and polybutylenes; polystyrene; natural or synthetic rubber; vinyl copolymers, such as polyvinyl chloride, plasticized or unplasticized, and poly(vinyl acetate); olefin copolymers, such as ethylene / methacrylate copolymers, ethylene / vinyl acetate copolymers, acrylonitrile / butadiene / styrene copolymers, and ethylene / propylene copolymers; acrylic polymers and copolymers; polyurethanes; polyethers; polyesters; and mixtures thereof. Preferably, the support layer is based on acrylic polymers, oriented or unoriented polyethylene (PE), polypropylene (PP). or bi-oriented, Polyimide, Polyurethane, Polyester such as Polyethylene terephthalate (PET), or paper.
[0248] According to one embodiment, the self-adhesive article obtained from the adhesive composition according to the invention comprises a permanent support layer coated with an adhesive layer. Preferably, the adhesive layer is further coated with a non-stick protective plastic film or paper, preferably silicone-coated.
[0249] According to another embodiment, the self-adhesive article obtained from the adhesive composition according to the invention comprises a non-permanent support layer which is made up of a first non-stick plastic film or protective paper, preferably silicone-coated, said layer being coated with an adhesive layer, itself also being able to be coated with a second non-stick plastic film or protective paper. This embodiment is particularly suitable for the assembly by gluing of windows, more particularly for the assembly of the rigid panel made up of double or triple glazing with the window frame. According to this embodiment, said non-permanent support layer is intended to be removed by the user at the time of implementation of the self-adhesive article for the purpose of assembling the window.
[0250] As an alternative to the non-stick protective film, the back side of the permanent support layer which is not coated with the adhesive layer, may have a non-stick surface, for example a silicone protective layer.
[0251] According to another embodiment, the permanent support layer is coated on both sides with an adhesive composition, which may be identical or different, at least one of the two adhesive compositions being according to the invention, advantageously leading to the manufacture of so-called double-sided tapes.
[0252] Preferably, the support layer has a thickness ranging from 10 microns to 50 mm, more preferably ranging from 10 microns to 20 mm, more preferably ranging from 20 microns to 10 mm, more preferably ranging from 20 microns to 1 mm.
[0253] In certain specific cases, it is necessary to carry out a surface treatment of the support layer to increase the adhesion of the adhesive layer during the coating step thereon.
[0254] The self-adhesive article according to the invention can thus bond two substrates. The substrate on which the self-adhesive article is intended to be applied (referred to as the “substrate to be bonded”) can be flexible or rigid. In particular, it can have the same flexibility properties as the support layer described above, so as to be wound and packaged in the form of a reel, for example as described above.
[0255] Alternatively, the substrate to be bonded may be rigid. In this case, the substrate cannot be wound and packaged in the form of a reel, for example as described above. The substrate to be bonded may for example be chosen from concrete, paper, polyolefin substrates, glass, ceramics and metals, especially aluminum.
[0256] The self-adhesive layer, which consists of the adhesive composition according to the invention in the crosslinked state, and which covers the support layer, in the self-adhesive article according to the invention can have a very variable thickness, ranging from 10 μm to 5000 μm, preferably.
[0257] A thickness ranging from 10 μm to 100 μm, preferably from 20 to 50 μm is more particularly preferred in the case of self-adhesive labels; while a thickness ranging in a much wider range of from 3 to 5000 μm can be encountered for self-adhesive tapes.
[0258] According to one embodiment, the self-adhesive article further comprises a protective anti-adhesive layer (“release liner” in English).
[0259] According to one embodiment, said anti-adhesive layer is applied to the adhesive layer, after crosslinking of the adhesive composition.
[0260] The support layer may be covered on one of its two faces, the rear face which is not coated with the adhesive layer, by a non-stick protective layer, for example by a silicone film. In this way, the self-adhesive article can be rolled up on itself and then unrolled without problem thanks to the absence of adhesion of the adhesive layer on the silicone face. Manufacturing process of the self-adhesive article
[0261] The present invention also relates to a method for manufacturing the self-adhesive article as defined above, said method being characterized in that it comprises:
[0262] - (a) preheating to a temperature between 40°C and 130°C of the com moisture-curable adhesive position, as defined above;
[0263] - (b) applying said composition by coating on a carrier surface;
[0264] - (c) crosslinking said composition, by heating to a temperature ranging from 50 to 200°C; then
[0265] - (d) laminating or transferring the layer of crosslinked adhesive composition on a support layer or on a non-stick protective film.
[0266] When the adhesive composition is, in accordance with the first embodiment described in point L, a single-component composition, it is said single-component composition which is, in accordance with step (a), preheated then in accordance with step (b), applied to the carrier surface, and finally, in accordance with step (c), crosslinked.
[0267] When the hot-curable adhesive composition is, in accordance with the second embodiment described in point II, a multi-component, and preferably two-component, composition, the preheating in accordance with step (a) relates to at least less composition U, and possibly composition V depending on the nature of the ingredients present in said composition V.
[0268] The preheating step (a) is then followed by a step (a1) of mixing compositions U and V at a temperature ranging from 40 to 130°C, the composition resulting from the mixture formed then being applied, in accordance with step (b) to the carrier surface, then crosslinked in accordance with step (c).
[0269] By "carrying surface" within the meaning of the present invention, it is necessary to understand either a belt conveyor covered with a non-stick layer, or a non-stick protective film ("release liner" in English), or a support layer.
[0270] In the case where the carrier surface is a non-stick protective film, the method of manufacturing the self-adhesive article according to the invention may comprise step (d) of transferring the crosslinked adhesive layer onto a support layer.
[0271] In the case where the carrier surface is a support layer or a non-stick protective film, the method of manufacturing the self-adhesive article according to the invention may also comprise step (d) of laminating the adhesive layer onto a non-stick protective film.
[0272] According to a preferred variant of the invention, step (d) of the above-described method consists of transferring the crosslinked adhesive layer onto a flexible support layer (which may be a plastic film) after cooling the crosslinked adhesive layer to a temperature below the degradation or softening temperature of the material making up the support layer.
[0273] According to one embodiment, the method for manufacturing the self-adhesive article according to the invention further comprises a step (e) of coating a second layer of adhesive composition according to the invention on the support layer followed by a step (f) of crosslinking the adhesive composition coated in step (e) by heating to a temperature ranging from 20 to 200°C. According to this embodiment, a double-sided self-adhesive article is obtained.
[0274] Coating step (b) can be carried out using known coating devices, such as for example a lip or curtain nozzle, or even a roller. It uses an adhesive composition weight ranging from 10 g / m2 to 5000 g / m2.
[0275] The grammage of adhesive composition required for the manufacture of self-adhesive labels may range from 10 to 100 g / m2, preferably from 20 to 50 g / m2. That required for the manufacture of self-adhesive tapes may vary in a much wider range from 3 to 5000 g / m2, preferably from 15 to 250 g / m2 per side.
[0276] According to one embodiment, the coated adhesive composition is further subjected, during step (c), to treatment in a humid atmosphere characterized by its humidity level and, in particular, in a gaseous environment where molecules of water are present between 10 and 200 g per m3 of gas.
[0277] Preferably, the humid atmosphere is an atmosphere in which from 2 to 100% of the molecules are water molecules, preferably from 3 to 50%, more preferably from 3 to 10% of the molecules are water molecules.
[0278] Humidity is expressed as the percentage of water per unit volume, which is the number of water molecules divided by the total number of molecules in a unit volume. Due to the linear nature of this scale, humidity is easily measured and controlled using, for example, PID (“Proportional-Integral-Derivative”) monitors. The weight percentage can be calculated by multiplying the percentage of the number of water molecules to the total number of molecules by a factor of 0.622. General information on humidity in various environments is described by W. Wagner et al., in “International Steam Tables - Properties of Water and Steam based on the Industrial Formulation IAPWS-IF97,.
[0279] The thermal crosslinking step has the effect in particular of creating - between the polymer chains with a hydrolyzable alkoxysilane end group of the adhesive composition and under the action of atmospheric humidity and possibly a crosslinking agent - siloxane type bonds which lead to the formation of a three-dimensional polymer network. The adhesive composition thus crosslinked is in particular a pressure-sensitive adhesive which gives the support layer coated with it the desirable adhesive power and tack.
[0280] Preferably, the coating is carried out uniformly on the support layer or on the non-stick protective layer but the coating can also be adapted to the desired shape of the final self-adhesive article.
[0281] According to one embodiment, the coating with the adhesive composition is carried out on at least a portion of the two faces of the support layer. If both faces of the support layer are coated, the adhesive composition may be identical or different on both faces, and the grammage may be identical or different on both faces.
[0282] According to one embodiment of the invention, the self-adhesive article comprises an adhesive layer on at least a portion of one face or on at least a portion of both faces of the support layer, said adhesive layer(s) being optionally coated with a non-stick protective layer. According to one embodiment, the self-adhesive article comprises two non-stick protective layers on each of the two adhesive layers. In this case, the two protective layers may be made of identical or different materials and / or they may have an identical or different thickness.
[0283] According to a preferred variant of the method for manufacturing the self-adhesive article according to the invention, using the multi-component adhesive composition such as defined previously, step (b) of application by coating on the carrier surface, for example on the support layer (96), is implemented by means of a hot application installation (20) of said adhesive composition, the installation comprising: - a nozzle (50) for applying the multi-component adhesive composition; - a line (88a) for supplying composition U included in the composition multi-component adhesive position to be applied in fluid form; - a line (66a) for supplying the composition V included in the multi-component adhesive composition to be applied in fluid form; - a line (88) for supplying the nozzle (50) with the multi-component adhesive composition to be applied in fluid form; and - a mixer (30) for mixing at least compositions U and V of the multi-component adhesive composition;
[0284] said step (b) comprising: - supplying the feed line (88a) with at least composition U; - supplying the feed line (66a) with at least composition V; - mixing at least composition U and composition V of the multi-component composition using a mixer (30); and - hot application of the mixed multi-component adhesive composition (80) to a support layer by means of the application nozzle (50).
[0285] The mixer may be a static mixer or a dynamic mixer.
[0286] Preferably, the static or dynamic mixer must be able to be temperature-regulated. Preferably, the mixer (30) is a dynamic mixer, advantageously allowing high shear mixing, and obtaining better homogeneity of the adhesive composition resulting from the mixing of at least compositions U and V of the multi-component composition.
[0287] The mixer (30) can be arranged between the supply lines of at least the compositions U (88a) and V (66a), and the supply line (88), and can allow the homogeneous mixing of the compositions constituting the multi-component adhesive composition, in particular two-component.
[0288] The method according to the invention comprises mixing at least composition U and composition V of the multi-component composition using a mixer (30). The mixing step may be a mixing of composition U with composition V, and optionally with one or more additional composition(s) of the multi-component composition (for example a composition W).
[0289] The installation may comprise heating means (44) capable of being arranged at the level of a storage tank (82) comprising the composition U or the composition V or another additional composition of the multi-component composition, to raise said composition to a pumping temperature, preferably at least composition U is raised to a pumping temperature of between 50°C and 140°C, preferably of between 80°C and 120°C, more preferably of between 90°C and 110°C.
[0290] Preferably, the multi-component adhesive composition is applied (after mixing at least compositions U and V) at a temperature between 50°C and 140°C, preferably between 60°C and 120°C, more preferably between 75°C and 110°C.
[0291] [Fig.l] shows a schematic representation of an embodiment of an installation 20 capable of implementing the method of manufacturing the self-adhesive article, according to the invention.
[0292] According to one embodiment, due to the at least double supply, the composition V (66) is separated from the composition U (68), up to the mixer (30) arranged between the supply lines of at least the compositions U (88a) and V (66a) on the one hand and the supply line (88) of the multi-component adhesive composition to be applied, on the other hand. In other words, the mixer (30) is in line and allows the performance of a step of homogeneous mixing of the compositions (66) and (68) supplied separately. The injection of the composition V (66) into the composition U (68) is carried out at the mixer (30), as illustrated for example in [Fig.l], to allow the immediate mixing of these compositions.
[0293] The different compositions constituting the multi-component adhesive composition according to the invention can be completely separated, that is to say that each composition is supplied separately to the hot application installation (20). In particular, the injection of composition U (68), composition V (66), and any additional composition(s) of the multi-component adhesive composition, is carried out at the mixer (30).
[0294] In the installation according to the invention, the composition U (68) can be heated in the storage tank (82) using a heating means (44), without causing the crosslinking of the composition U (68) due to the separation of the composition V (66), comprising at least the crosslinking catalyst. The heating in the storage tank (82), preferably represented in the form of a barrel, makes it possible in particular to reduce the viscosity of the composition U (68), to facilitate pumping into the installation (20), such as using a pump (46), before any contact with the separated composition V (66).
[0295] This heating means (44) (preferably being a heating plate) contributes in particular to bringing the composition U (68) to the application temperature. The application temperature corresponds in particular to a temperature where the composition adhesive to be applied has a viscosity low enough to allow the application, in other words the coating, of the mixed multi-component adhesive composition (80) on the surface (96).
[0296] Indeed, after mixing compositions V (66) and U (68), the multi-component adhesive composition (80) is formed and can be applied hot to the support (96) using an application nozzle (50). An application temperature of the multi-component adhesive composition (80) can thus correspond to a temperature where the viscosity of the multi-component adhesive composition is less than or equal to 50 Pa.s, preferably less than or equal to 10 Pa.s. For example, the multi-component adhesive composition (80) can have a viscosity of 5 ± 1 Pa.s at an application temperature ranging from 60°C to 120°C. Following the application of the multi-component adhesive composition (80) to the surface (96), the coated support (98) is subjected to a controlled temperature, and optionally to a controlled humidity level, to allow the crosslinking of the multi-component adhesive composition.
[0297] The controlled temperature can be obtained using an oven or an enclosure. The controlled temperature corresponds to a crosslinking temperature of the multi-component adhesive composition (80) and is for example between 50°C and 200°C, preferably between 80°C and 160°C, in particular between 100°C and 150°C.
[0298] Similarly, composition V (66) can also be heated before mixing it with composition U (68) without risk of crosslinking before mixing them. The same applies to any composition(s) of the multi-component composition according to the invention.
[0299] Heating all of the separate compositions V (66) and U (68) before mixing them makes it possible in particular to bring these components to the application temperature without risk of crosslinking before mixing them in the mixer (30).
[0300] The self-adhesive article according to the invention can finally be used in a bonding method which is also the subject of the invention, characterized in that it comprises the following steps:
[0301] a) removing the non-stick protective layer, when such a layer is present;
[0302] b) applying the self-adhesive article to a surface of a product; and
[0303] c) applying pressure to said article.
[0304] In step b), the self-adhesive article is applied so that the self-adhesive part of the article (formed by the self-adhesive layer) faces the surface of the product.
[0305] According to an embodiment in which the self-adhesive article is a double-sided article, the bonding method further comprises a step in which either a second surface of a product is applied to the article bonded to the first surface of a product, or the article adhered to the first surface of a product is applied to a second surface of a product. Uses
[0306] The present invention also relates to the use of a compound (C) as defined above, in an adhesive composition comprising: - a silylated polymer (A) as defined above, - a tackifying resin (B) as defined previously;
[0307] to improve the aging resistance of the composition after crosslinking.
[0308] The ingredients and characteristics (including preferred modes) described above for the composition also apply for the aforementioned use, without it being necessary to repeat everything.
[0309] In the context of the invention, by "between x and y", or "ranging from x to y", is meant an interval in which the limits x and y are included. For example, the range "between 1% and 10%" includes in particular the values 1% and 10%.
[0310] The following examples illustrate the invention without, however, limiting it. EXPERIMENTAL PART
[0311] The following products were used:
[0312] - GENIOSIL ® STP-E30, available from WACKER: polypropylene glycol terminated by two alpha silane functions of methyl dimethoxy type with a number-average molecular mass of approximately 24,000 g / mol;
[0313] - DERTOPHENE ® T105, available from DRT: tackifying resin type phenolic terpene;
[0314] - IRGANOX ® 1010, available from BASF: phenol-type antioxidant cluttered;
[0315] - IRGANOX ® 245, available from BASF: phenol-type antioxidant cluttered;
[0316] - TES 40WN: tetra ethoxy orthosilicate from Wacker;
[0317] - TyZOR TnBT: titanium butoxide, M = 340 g / mol from the company Dorf Kétal;
[0318] - XL 33: moisture absorber marketed by Wacker.
[0319] Measurement of T s ■.
[0320] The glass transition temperature (Tg) was measured by dynamic mechanical analysis (DMA).
[0321] The following conditions were used:
[0322] - the T-scans (1Hz) are carried out on an MCR302 rheometer from Anton Paar, equipped with a CTD450 oven. Liquid nitrogen can be used as gas.
[0323] - the sample consists of a 500 gsm monolayer of the composition adhesive after aging for 7 days at 50°C;
[0324] - 10 mm parallel plates are used;
[0325] - a gap is defined by the thickness of the sample, between 500 and 1000 microns
[0326] - the samples are placed at 40°C in the rheometer with a pressure between between 1 and 2 N;
[0327] - the temperature ramp is as follows:
[0328] - interval 1: insertion at 40°C, pressure 1 N;
[0329] - interval 2: cooling to -40°C, pressure of 0.5N;
[0330] - interval 3: stabilization at -40°C for 1 min;
[0331] - interval 4: heating at 5°C / min down to -10°C (oscillation at 0.005%, 1 Hz, ON);
[0332] - interval 5: heating at 5°C / min up to 150°C (oscillation at 0.005%, 1 Hz, ON).
[0333] Example 1: Preparation of Reference Composition Cl
[0334] Composition Cl of Table 1 is prepared in two steps. 1. Part A
[0335] Part A of composition C1 is prepared by first introducing the tackifying resin Dertophene® T105 into a glass reactor and mixing with the antioxidant for approximately one hour (reactor temperature rise time and including at least 30 minutes at a temperature 15-40°C above the softening point of the tackifying resin, i.e. approximately 130°C)
[0336] Then, once the resin is well melted, a portion of the GENIOSIL® STP-E30 (silane-modified polymer) is added at 140°C under vacuum (0 mbar). Then the temperature is reduced by 20°C, before adding the second portion of GENIOSIL® STP-E30. The mixture is then gradually cooled to 90°C under vacuum to extract all traces of water and avoid hydrolysis of the silane-modified polymer. The polymer additions are carried out under a nitrogen flow.
[0337] The mixture is stirred under vacuum for 10 minutes, then cooled for storage in a cartridge before use. 1. Preparation composition Cl
[0338] Composition C1 is prepared by preheating Part A above to 100°C for at least 30 minutes.
[0339] Then, the Tyzor TnBT catalyst is added with stirring (2000 rpm) for 5 minutes.
[0340] The composition Cl is detailed in Table 1 below.
[0341] Example 2: Preparation of composition C2 (invention)
[0342] Composition C2 is prepared according to the same protocol as reference composition Cl (example 1), except that TES40WN is added with the Tyzor TnBT catalyst (without initial premix).
[0343] Composition C2 is detailed in Table 1 below.
[0344] Example 3: Preparation of PET support layer coated with the composition crosslinked at a weight of 60 g / m2
[0345] A rectangular sheet of siliconized PolyEthyleneTetraphthalate (PET) (non-stick layer) measuring 21 cm by 29.7 cm is used as the support layer.
[0346] Composition Cl (or C2) is preheated to a temperature close to 100°C and introduced into a cartridge from which a bead is extruded which is deposited near the edge of the sheet parallel to its width.
[0347] The composition contained in this bead is then distributed over the entire surface of the sheet, so as to obtain a uniform layer of substantially constant thickness. For this, a film puller (also called a film-mograph) is used, which is moved from the edge of the sheet to the opposite edge. A layer of composition corresponding to a weight of 60 g / m2 is thus deposited, which represents a thickness of approximately 60 μm.
[0348] The PET sheet thus coated is then placed in an oven at 140°C and under a humid atmosphere (2.4% relative humidity) for 5 minutes to crosslink the composition, then laminated onto a layer of PolyEthylene Terephthalate (PET) 50 μm thick (Mylar) and measuring 21 cm by 29.7 cm, consisting of a sheet of silicone film, rectangular and of the same dimensions.
[0349] The three-layer obtained is subjected to the 3 tests described below.
[0350] After the coating has crosslinked, it is covered with a release liner (non-stick protection) and placed either at 23°C or in an oven at 50°C for 7 days (to evaluate the final performance of the coating whose crosslinking has been optimized).
[0351] 180° peel test on stainless steel plate:
[0352] The adhesive power is evaluated by the 180° peel test on a stainless steel plate as described in FINAT method No. 1, published in the FINAT Technical Manual 6th edition, 2001. FINAT is the international federation of manufacturers and converters of self-adhesive labels. The principle of this test is as follows.
[0353] A test piece in the form of a rectangular strip (2.54 cm x 15 cm) is cut from the three-layer obtained previously.
[0354] It is then fixed over half of its length (after removal of the corresponding portion of protective anti-adhesive layer) on a substrate consisting of a stainless steel plate. The assembly obtained is left for 10 minutes at room temperature (23°C) (“dwell time” or wettability time). It is then placed in a traction device capable, from the end remaining free of the rectangular strip, of peeling or detaching the strip at an angle of 180° and with a separation speed of 300 mm per minute. The device measures the force required to detach the strip under these conditions.
[0355] The corresponding result is expressed in N / cm and shown in Table 1.
[0356] Evaluation of heat resistance - “SAFT” test method on stainless steel:
[0357] The temperature retention of the adhesive power is evaluated by the test for determining the temperature causing the adhesive joint to break under static shear. This test is also known by its English name of “Shear Adhesion Failure Temperature” (or SAFT).
[0358] A test piece in the form of a square strip (2.54 cm x 7.5 cm) is cut from each of the three-layer film above. After removing the entire protective layer (or "release liner" in English), a square portion of 2.54 cm on each side located at the end of the adhesive strip is fixed to a sanded stainless steel plate, the unglued part of the 5 cm long strip being located below the plate. After thermal equilibration at 23°C for 1 h, the test plate thus obtained is placed, using a suitable support, in a substantially vertical position (2° from the vertical) in an oven at 23°C. The part of the strip that remains free is connected to a mass of 1 kg, the entire device then remaining in the study for the entire duration of the test. The SAFT value is then measured in accordance with the Finat 8 test method with an oven temperature rise of 0.5°C per minute.The temperature at which the strip detaches from the plate following the rupture of the glue joint under the effect of this stress is noted.
[0359] Shear strength test at 125°C on stainless steel
[0360] The internal cohesion of the adhesive is evaluated by the shear test at 125°C.
[0361] The preparation of the test piece is done exactly as for a SAFT. The difference between the 125°C shear and the SAFT is that the sample, subjected to a weight of 1 kg, is placed in a temperature-controlled oven at 125°C. The result of the shear test corresponds to the time of resistance to the stress (weight and temperature) before the weight is no longer retained by the adhesive.
[0362] The time after which the strip detaches from the plate following the rupture of the glue joint under the effect of this stress is noted.
[0363] The results are expressed in the following Table 1 for different aging temperatures (23°C or 50°C for 7 days): Composition Cl (reference - comparative) Composition C2 (invention) Composition (%w) Dertophene T105 54.14 48.72 Irganox 1010 0.45 0.40 Irganox 245 0.45 0.40 TES 40WN / 10 STP-E30 44.31 39.87 XI 33 0.4 0 36 TnBT 0.25 0.25 100 100 Results 7 days at 23°C 180° peel (N / cm) 9.68 5.8 Shear / Shear strength at 125°C (in hours)- 1kg 24.3 131.3 SAFT (°C) - 1kg 181°C >200°C Tg (°C) Tscan 1Hz -2.5 1.6 7 days at 50°C Shear / Shear strength at 125°C (in hours)- 1kg 28.8 141 SAFT (°C) - 1kg 183°C >200°C
[0364] It is clear from this table that the composition C2 according to the invention advantageously provides a high shear strength compared to the reference composition Cl (131h for C2 compared to 24.3h for Cl), even after aging at 50°C.
[0365] The table also shows that the adhesive strip from composition C2 advantageously resists up to more than 200°C compared to the adhesive strip from composition Cl (181 / 183°C).
[0366] These results demonstrate good resistance of composition C2 to aging under restrictive temperature and humidity conditions.
Claims
Claims
1. A moisture-curable adhesive composition comprising: - at least one silylated polymer (A); - a tackifying resin (B); - at least one compound (C) chosen from the group consisting of • compounds of formula (Fl) and their oligomeric / polymeric derivatives: R0-O-[-Si(OR°)2-O-]t-R0 (Fl) in which: - R° is independently chosen from alkyls and aryls, - t represents an integer ranging from 1 to 20, preferably from 1 to 7 ; compounds of formula (F2): (F2) in which: - R'° is independently selected from alkyl groups comprising from 1 to 10 carbon atoms, - u is an integer ranging from 3 to 5000, • aminopolysiloxane compounds; and • their mixtures; said composition being characterized in that it has a glass transition temperature ranging from -25°C to 20°C.
2. A moisture-curable adhesive composition according to claim 1, characterized in that it has a glass transition temperature of from -25°C to 20°C, preferably from -20°C to 15°C.
3. Moisture-crosslinkable adhesive composition according to any one of claims 1 or 2, characterized in that the silylated polymer (A) corresponds to one of the formulae (II'), (III') or (IV'): O—r|-O—fî— (II') 4 --¾ ? 4 (R'OA 4^ VSi—R—O— R—O--R— Sî(R ' ^(OR^Kr. (HD (IV') in which: - R1 represents a divalent hydrocarbon radical comprising from 5 to 15 carbon atoms which can be aromatic or aliphatic, - R3 represents a linear or branched divalent alkylene radical comprising from 1 to 6 carbon atoms, preferably from 1 to 3 carbon atoms, - X represents a divalent radical chosen from -NH-, -NR7- or -S-, - R7 represents a linear or branched alkyl group comprising from 1 to 20 carbon atoms and which may also comprise one or more heteroatoms, - R4 represents a linear or branched alkyl group comprising from 1 to 4 carbon atoms, with the possibility that when there are several R4 radicals, the latter are identical or different; - R5 represents a linear or branched alkyl group comprising from 1 to 4 carbon atoms, with the possibility that when there are several R5 radicals, the latter are identical or different, with the possibility that two OR5 groups can be engaged in the same cycle; and - p is an integer equal to 0, 1 or 2, preferably equal to 0 or 1, - R2 represents a saturated divalent hydrocarbon radical or unsaturated, linear or branched optionally comprising one or more heteroatoms, such as oxygen, nitrogen, sulfur, silicon, and preferably having a number-average molar mass ranging from 100 g / mol to 48,600 g / mol, more particularly from 300 g / mol to 38,600 g / mol, and - n is an integer greater than or equal to 0.
4. Moisture-curable adhesive composition according to claim 3, characterized in that R2 is a divalent radical derived from a polyether, preferably from a poly(oxyalkylene) diol, and even more particularly from a polypropylene glycol.
5. Moisture-crosslinkable adhesive composition according to any one of claims 1 to 4, characterized in that the tackifying resin (B) is chosen from terpene resins, and even more preferably from terpene-phenolic resins.
6. Moisture-crosslinkable adhesive composition according to any one of claims 1 to 5, characterized in that the compound (C) is chosen from the compounds of formula (F1) and their oligomeric / polymeric derivatives.
7. Moisture-curable adhesive composition according to claim 6, characterized in that the compounds of formula (F1) and their oligomeric / polymeric derivatives are those in which: - R° is chosen from ethyl, n-propyl, butyl, or isopropyl; and / or -1 represents an integer ranging from 1 to 20; more preferably in which: - R° is an ethyl; and / or -1 is an integer ranging from 2 to 7.
8. Moisture-crosslinkable adhesive composition according to any one of claims 1 to 7, characterized in that the compound (C) is chosen from tetra-ethoxyorthosilicate, tetra-propoxyorthosilicate, tetra-isopropoxyorthosilicate, tetra-butoxyorthosilicate, their oligomeric / polymeric derivatives, and their mixtures, and even more preferably from tetra-ethoxyorthosilicate, their oligomeric / polymeric derivatives, and their mixtures.
9. A moisture-curable adhesive composition according to any one of claims 1 to 8, characterized in that it comprises from 1% to 50% by weight of compounds (C), preferably from 4% to 40% by weight, and even more preferably from 5% to 20% by weight relative to the total weight of said composition.
10. Moisture-crosslinkable adhesive composition according to any one of claims 1 to 9, characterized in that it comprises a carbonated filler content of less than or equal to 15% by weight, more preferably less than or equal to 10% by weight, and even more preferably less than or equal to 5% by weight, relative to the total weight of said composition.
11. Moisture-curable adhesive composition according to any one of claims 1 to 10, characterized in that it does not comprise a carbonated filler.
12. A moisture-curable adhesive composition according to any one of claims 1 to 11, characterized in that it is a pressure-sensitive self-adhesive (PSA) composition.
13. Moisture-crosslinkable adhesive composition according to any one of claims 1 to 12, characterized in that it has, after crosslinking, an adhesive power at 180° (peel at 180°) at 23°C greater than or equal to 0.4N / cm, determined according to the FIN AT method No. 1 of 2001.
14. Moisture-curable adhesive composition according to any one of claims 1 to 13, characterized in that it is in the form of a multi-component composition comprising: - a composition U (as 1st component) comprising: - the silylated polymer(s) (A); and - the tackifying resin(s) (B); - optionally the compound(s) (C), and - a composition V (as 2nd component) comprising: - the compound(s) (C); the optional catalyst (D) being included in composition V or in a composition W (3rd component).
15. Self-adhesive article comprising a support layer coated with a self-adhesive layer, characterized in that said self-adhesive layer consists of the adhesive composition as defined according to any one of claims 1 to 13, in the crosslinked state.
16. Use of a compound (C) as defined in any one of claims 1 to 14, in an adhesive composition comprising: - a silylated polymer (A), - a tackifying resin (B); to improve the aging resistance of the composition after crosslinking.
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