WO2020067877A1

WO2020067877A1 - Silyl modified polymer two-component composition comprising a zeolite booster

Info

Publication number: WO2020067877A1
Application number: PCT/NL2019/050575
Authority: WO
Inventors: Rudolph Frank DE BLOCK; Wilco Bernardus WENNEKES
Original assignee: Strongbond B.V.
Priority date: 2018-09-28
Filing date: 2019-09-05
Publication date: 2020-04-02
Also published as: EP3856854A1; NL2021734B1

Abstract

The present invention is in the field of an improved silyl modified terminated polymer used in a composition for use as a sealant or adhesive, and especially in combination with a specific booster comprising additives. The sealant may be used in various applications, such as in building and construction, industry, transportation, solar energy, marine, waterproofing, and so on.

Description

SILYL MODIFIED POLYMER TWO-COMPONENT COMPOSITION

COMPRISING A ZEOLITE BOOSTER

FIELD OF THE INVENTION

The present invention is in the field of an improved silyl modified terminated polymer used in a composition as sealant or as adhesive, and especially in combination with a specific booster comprising additives. The sealant or additive may be used in various applications, such as in building and construc tion, industry, transportation, solar energy, marine, waterproofing, and so on.

BACKGROUND OF THE INVENTION

Silyl modified polymers (SMPs), also referred to as modified- silane (MS) polymers, relate to so-called silane (also referred to as silyl} terminated polymers. This is a special class of polymers, polymers being large molecules having many repetitive units in a middle and long section thereof, which have as an end group of the long middle section, also referred to as a termi nating group, a silyl type molecule. SMPs are main components in sealant and adhesive products, which may be solvent-free. These products are typically (iso)cyanate free. Sealant products manu factured with silyl modified polymers have good characteristics, such as adhesion on a wide range of substrate materials, and have good temperature and UV resistance. This makes these prod ucts applicable in a wide range of applications.

The silyl modified polymers can be formed using chemistry techniques. On application the products, such as an SMP sealant, cure from a liquid or gel state to an elastomer. Curing entails cross-linking by the hydrolysis and subsequent condensation of silyl ethers. Cross-linking improves certain characteristics of the final material.

The present invention makes use of a specific type of polymer, such as known as Kaneka's MS Polymer™ and other silyl-ter- minated polymers. Its unique properties enable MS Sealant (the sealant based on Kaneka MS Polymers) to deliver outstanding per formances for a large variety of markets such as construction, industry, transportation, flooring, waterproofing, DIY and many others. As a middle section it contains a functionalized poly ether backbone with methoxysilane terminal groups. It provides excellent performances and makes MS Polymer-based products unique and beneficial.

A broad range of MS Polymer™ grades are available. These may differentiate in degree of functionalization (number and nature of groups attached to the backbone) and backbone structure in a wide viscosity range. Typically a dimethoxysilyl terminated polyether (DMS MS) or trimethoxysilyl terminated polyether (TMS MS) is used.

Zeolites are aluminosilicate minerals with a porous structure. They are used as commercial adsorbents and catalysts. Rapidly heating of the material results in large amounts of steam being produced from water that had been adsorbed by the material. A classic reference for the field is Breck's book

Zeolite Molecular Sieves: Structure, Chemistry, And Use. Zeolites occur naturally and are also produced industrially on a large scale. Zeolites are solids with pore sizes in the order of magnitude of several Angstroms. Many unique zeolite frame- works have been identified, and over also many naturally oc curring zeolites are known; in addition it is predicted that millions of hypothetical zeolite structures are possible. Zeolite structural groups may be classified according to the Nickel-Strunz classification (class 09. G) which is primarily a chemical based classification. In practice zeolites in view of their pore sizes are often only referred to as such (i.e. "pore size in A zeolite") . The zeolite used by Saba in prior art applications is a 3A zeolite.

A MS sealant can be used as a one-component adhesive or as a two-component adhesive. For the two-component adhesive a booster may be added. The booster is intended to support strength buildup and cure speed. The booster typically contains water and is mixed with the MS sealant just before application. As a conse quence of mixing the booster into the sealant the cure of the sealant is no longer limited by diffusisn af »aistu3½ fvm fete air as the booster provides water; the mixture shows bulk cure behavior. The prior art booster that is produced by Saba contains a molecular sieve (zeolite) to store the water and to pre vent phase separation of the water during storage of the booster. However curing time and strength build-up is rather slow, and at least to slow for certain application where a fast strength build-up is required, such as for adhering a workpiece, such as a car window, a car panel, etc.

WO 2018/074925 A1 recites a two component adhesive, a method of making said adhesive, and use of said adhesive. The first component of the two component adhesive comprises a silyl modified polymer and a co-catalyst, wherein the co-catalyst typ ically is a primary or secondary amino silane, which is protected from water, whereas the second component comprises a si lyl modified polymer and/or hybrid polymer, a molecular sieve, and water. EP 0264 097 A2 recites an improved adsorbent, essentially impermeable to oxygen and nitrogen but permeable to water vapor, and to sealants incorporating said adsorbent. The zeolite adsorbent, and sealants prepared from the zeolite, are particularly useful in the fabrication of thermal insulating glazed windows having a sealed air pocket. US 9,994,744 B2 recites a moisture-curing sealant comprising a) at least one silane-func tional polymer and b) at least one catalyst for the crosslinking of the silane-functional polymer, said sealant being free of or- ganotin compounds and having, in the cured state, a secant modu lus at 100% elongation and 23° C. These compositions may be considered as examples of the prior art.

It is therefore an object of the present invention to pro vide a MS sealant which functions better for given purposes, without jeopardizing functionality and advantages.

SUMMARY OF THE INVENTION

The present invention relates to an improved modified si lyl terminated polymer sealant according to claim 1, a kit of parts according to claim 14, and a use thereof according to claim 15. Using the present zeolite^ such as a 5Ά zeolite^ in the booster formulation instead of the standard 3A zeolite, an unexpected and not well understood improved balance be- tween skin formation time and bulk cure speed is achieved. The present zeolite, compared to prior art zeolites, is considered to support the cure speed and bulk formation by driving a reac tion towards the end product. The strength build-up in the bulk increases significantly, as determined by both rheological and tensile tests, without affecting the skin formation time. The booster contains water and is typically mixed with the MS sealant before application. The cure of the sealant is now no longer limited by diffusion of moisture from the air; the mixture shows bulk cure behavior. The booster that is pro duced by Saba contains a molecular sieve (zeolite) to store the water and to prevent phase separation of the water from the polymer during storage of the booster. For application it is preferred that the zeolite is in a fine powdery form and not in a usually provided pallet form. Especially when using the powdery form, the described results were obtained.

The present booster comprises 10-60 wt.% zeolite, prefera bly 20-50 wt.%, such as 30-45 wt.%, e.g. 40 wt.%. As the booster is mixed with the first component in a ratio of 1:100- 15:100 wt . booster :wt. first component, an amount of booster in a final composition is about 1-13 wt.%, based on the total composition. The booster may further comprise 30-90 wt.% polymer or plasticizer, or a mixture thereof (0.5-12 wt.% based on the total com position), preferably 40-60 wt.%, such as 45-50 wt.%, and small amounts of water, typically less than 15 wt.%. The polymer may be the same as in the first component, or different, or both. Zeolites may suitably be selected from Zeolites with chains of T10O20 tetrahedra, wherein T is selected from Si and A1 and combi nations thereof, such as clinoptilolite, heulandites, barrerite, stellerite, stilbites, brewsterites, zeolites with chains of 6- membered rings such as tabular zeolites, e.g. bellbergite, bikitaite, chabazites, dachiardites, epistilbite, erionites, faujasites, ferrierite, gmelinite, herschelite, levynes, Linde type X, Linde type Y, maricopaite, mordenite, offretite, SSZ-13, wenkite, willhendersonite, zeolites with T5O10 units {T as above) , such as edingtonite, gonnardite, kalborsite, natrolite, mesolite, paranatrolite, scolecite, tetranatrolite, and thom- sonites, zeolites with chains of single connected 4-membered rings, such as analcime, goosecreekite, Laumontite, leucite, montesommaite, pollucite, wairakite, and yugawaralite, zeolites with chains of double connected 4-membered rings, such as amicite, boggsite, garronite, gismondine, gobbinsite, harmotome, Linde type L, mazzites, merlinoite, paulingites, perlialite, and phillipsites , and cowlesite, Linde type A, pentasil, tschernich- ite, CaA zeolites, CaX zeolites, NaX zeolites, NaY zeolites, wherein the pore size of said zeolite is from 0.4-2.1 nm {4-21 A) , and if required {typically not) a remainder water. It is not well understood why smaller pore sizes, as typically used in the prior art, do not provide the present beneficial effects.

The zeolite is in powder form and has an average particle size of smaller than 100 pm, preferably 1-60 pm, more preferably 10-50 pm, even more preferably 15-40 p , such as 20-30 pm. It has been found that finely formed zeolite particles (< 100 p ) function significantly better in terms of curing speed, strength build-up, and appearance of the final cured product.

The main component of the sealant is a modified silyl terminated polymer. This polymer is present in an amount of 10-60 wt.%, based on a total weight of the sealant. It is preferred to use 20-50 wt.% polymer, such as 30-45 wt.%, e.g. 35-44 wt.%.

As a further component a filler is used in an amount of 10-50 wt.%, preferably 20-45 wt.%, more preferably 30-40 wt.%.

As an optional component a plasticizer is added in an amount of 0-30 wt.%, preferably 1-20 wt.%, more preferably 2-15 wt.%, even more preferably 3-10 wt.%, such as 4-7 wt.%.

Further additives may be added in an amount of 0-15 wt.%, preferably 1-10 wt.%, more preferably 2-8 wt.%, even more pref erably 3-7 wt.%, such as 4-6 wt.%.

The invention is mainly characterized by a specific selection of a zeolite, in combination with the silyl modified polymer. In principle also a combination of the present zeolites may be used, with a total weight thereof in the above range (s) (typically 1-5 wt . %) .

Thereby the present invention provides a solution to one or more of the above-mentioned problems.

Advantages of the present description are detailed through^¬ out the description.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates in a first aspect to a seal ant according to claim 1.

It is noted that the present zeolite it typically provided in a dried form, and then mixed with further booster components, such as water.

In an exemplary embodiment of the present sealant the pore size of said zeolite may be from 0.42-1.5 nm (4.2-15 A), preferably from 0.45-1.2 nm (4.5-12 A), more preferably from 0.47-1.0 nm (4.7-10 A), such as from 0.49-0.7 nm (4.9-7 A).

In an exemplary embodiment of the present sealant the zeolite (dry) may be grinded, milled, sieved, and combinations thereof.

In an exemplary embodiment of the present sealant the filler may be selected from chalk, precipitated chalk, coated precipi tated chalk, silica, carbon black, and combinations thereof. It preferably is a calcium carbonate based composition.

In an exemplary embodiment of the present sealant the plasti cizer may be selected from benzoates, phthalates, tereph- thalates, polyols, such as polypropylene glycol (PPG) , hydrogenated versions of phthalates, terephthalates, and benzoates, and combinations thereof. In view of toxicity polyols, tereph thalates and benzoates are preferred. Examples of suitable ter ephthalates are dibutyl terephthalate, dipropyl terephthalate, and dipentyl terephthalate. Examples of suitable benzoates are mono-esters from benzoic acid and a Cs-Cie alcohol, preferably wherein the alcohol is a C9-C₁₁ alcohol, preferably a C₁₀ alcohol. Suitable polyols are for example PPG-2000, PPG 1000, and PPG2500.

In an exemplary embodiment of the present sealant the addi^¬ tives may be selected from catalysts, co-catalysts, rheology control agents, pigments, pigment pastes, HALS, UV stabilizers, antioxidants, adhesion promotors, drying agents, and combina^¬ tions thereof.

In an exemplary embodiment of the present sealant the polymer may comprise a functionalized polyether backbone. The molecular weight average mass of the polymer is from 2000-50000 Da.

In an exemplary embodiment of the present sealant the poly ether backbone may comprise methoxy or ethoxy silane terminal groups, typically at all ends, each comprising 1-3 methoxy- groups, typically two or three methoxy-groups .

In an exemplary embodiment of the present sealant the modi^¬ fied silane polymer may comprise one or more -An-D-SiXYZ end groups, wherein A is a divalent linking group comprising at least one hetero atom, such as S,N,0,P, and Si, preferably 0. D is a divalent hydrocarbon residue with 1-12 C-atoms, preferably 2-8 carbons, such as 3, 4, 5 or 6 carbon atoms. X, Y, Z are each independently substituents on the Si atom. They are inde

pendently selected from CI-CB alkyl, CI-CB alkoxy, Ci-Ce acyloxy, preferably C₂-C5 alkyl, C₂-C₅ alkoxy, and C₂-C₅ acyloxy. At least one of the substituents X, Y, Z is a C1-C3 alkoxy or Ci-Cg acyloxy. And further n is 0 or 1.

In an exemplary embodiment of the present sealant A may be selected from oxygen, -NR'-, amide, carbamate, urea, imino, car- boxylate, carbamoyl, amidino, and carbonate, wherein R'=H or Ci- C₄ alkyl, preferably oxygen or -NH-.

In an exemplary embodiment of the present sealant D may be selected from alkyl residues, such methyl, ethyl, and n-propyl .

In an exemplary embodiment of the present sealant the polymer may be selected from at least one of MS-polymers™, dimethoxy si- lyl terminated polyether, trimethoxy silyl terminated polyether, S203H, S303H, S227 , S327, SAX 220, SAX 260, SAX350, SAX400,

SATO 10, SAX015, SAX115, SAT145, AX602, MAX923, MAX951, SAX750, SAX510, SAX520, SAX 530, SAX540, SAX580, SAX590, MAX 451, MAX 480, MAX850; Desmoseal®, for example S XP 2458, S XP 2636, S XP 2749, S XP 2774, S XP 2821; Geniosil® for example STP-E10, STP- E15, STP-E30, STP-E35, Evonik Polymer for example ST47, ST 48,

ST 77, ST 61, ST 61 LV, ST 81, ST 80 and TEGOPAC® , for example Seal 100, Bond 150, and Bond 250.

In an exemplary embodiment of the present sealant the booster may comprise 30-80 wt . % silyl modified polymer or plasticizer, preferably 40-70 wt.% silyl modified polymer or plasticizer, such as 50-60 wt.% silyl modified polymer or plasticizer, and 1- 15 wt.% water, preferably 5-12 wt.% water, such as 7-10 wt.% wa ter, and 40-60 wt.% zeolite.

In a second aspect the present invention relates to a use of the present sealant for sealing or bonding for increased

strength built up, for adhering a workpiece, such as a car win dow, a car panel, for buildings, such as homes, sheds, facto ries, offices, and high-rise buildings, road-infrastructure, such as viaducts, bridges, and fly-overs, transport vehicles, such as cars, trucks, busses, trains, vans, motorhomes, caravans, and trailers, ships, such as yachts, ships, and boats, or for improving storage stability.

In a third aspect the present invention relates to a kit of parts comprising at least one of a present first component and a present second component according to the invention, wherein a ratio of first component : second component is 100:1 to 100:15 (wt./wt.), preferably 100:3 to 100:12, more preferably 100:8 to 100:11, such as 100:9-100:10.

The invention is further detailed by the accompanying figures and examples, which are exemplary and explanatory of nature and are not limiting the scope of the invention. To the person skilled in the art it may be clear that many vari ants, being obvious or not, may be conceivable falling within the scope of protection, defined by the present claims.

SUMMARY OF FIGURES

Figs. 1 shows zeolites. Fig. 2 shows strength build-up of sealants 2-5 ( rheometer

method) .

Fig. 3 shows strength build-up sealant 1 (rheometer method) .

Fig. 4 shows strength build-up sealant 1 (tensile test method) . Fig. 5 shows skin formation times experimental sealants 2-5 and boosters .

EXAMPLES /EXPERIMENTS

The invention although described in detailed explanatory context may be best understood in conjunction with the accoiti- panying examples and figures.

Experimental

Setup: -The experimental work described here is a selection from two different studies where the pore size of the zeolite was used as a variable. The other (sealant- and booster-) variations are not relevant for the purpose of this document and therefore not described in detail. In total, 5 MS sealant formulations are used: referred to as experimental sealant 1-5. A total of four booster compositions were investigated, see Table I.

Table l: Booster formulations; formulations 3 and 4 comprise a rheology additive.

Table 2: composition of sealants used. Booster 3A Booster 5A

MS-polymer 50 50

Zeolite 3A 40

Zeolite 5A 40

Water 10 10

Table 3: booster compositions.

All sealants 1-5 were tested with both (3A and 5A) boosters.

Strength build-up by rheometer:

The strength build-up was determined using a series of stress sweeps with different waiting times. Using this method, a yield stress versus time plot can be obtained making it possible to compare cure speeds.

Strength build-up by tensile tester:

The tensile strength was measured as a function of time using ISO 37 type 2 dumbbells. When preparing the dumbbells, they were covered with a PE foil, minimizing the influence of the air and mimicking bulk cure behavior.

Skin formation time:

The so-called BK-recorder was used to determine the skin for mation time. A 450 pm thick layer of sealant/booster mixture was applied on a glass substrate and a 0,85 mm thick needle carrying 10 g of weight travels through the applied layer with a velocity of 2,5 mm/min. When the layer of sealant/booster mixture is cured, the needle can no longer penetrate the sample and contin ues to travel, scratching the top of the sample. Distance can be converted to time and a value for skin formation time is ob tained. This test was carried out at 23°C and 50% relative hu midity.

Results

From Figure 5 it may be concluded that the sealant composi tion is as expected the main cause for variation in skin for mation times, rather than the booster composition. The skin for mation time is hardly influenced by the type of zeolite used in the booster. The pore size has at best a very limited effect on skin formation if any effect at all. The rheometer method strength build-up curves are given in Figure 2 for the sealants 2-4and Figure 3 for the sealant 1. Surprisingly, from these curves it can be concluded that the sealants mixed with the 5A zeolite containing booster show faster strength build-up than its 3A zeolite containing counter part. Also, the tensile test results (Figure 4) confirm the faster strength build-up for the 5A zeolite in the first 72 hours .

Claims

1. 2-component composition for use as adhesive or sealant comprising

a first component, the first component comprising

10 - 60 wt.% of a silyl modified polymer,

10 - 50 wt.% of filler,

0 - 30 wt.% of a plasticizer,

0 - 15 wt.% additives,

characterized in

a second booster component comprising 10-60 wt.% zeo lite, wherein the pore size of said zeolite is from 0.42-2.1 nm (4,2-21 A), and an optional remainder water, with the proviso that the second component does not comprises a catalyst or co catalyst, nor a reactive amine-functional group,

wherein the zeolite is in powder form and has an average parti cle size of < 100 p ,

wherein all wt.% are relative to a total weight of the first or second component of the sealant respectively.

2. Sealant according to claim 1, wherein the pore size of said zeolite is from 0.43-1.5 nm (4.3-15 A}, preferably 0.45-1.2 nm (4.5-12 A), more preferably from 0.47-1.0 nm (4.7-10 A), such as from 0.49-0.7 nm (4.9-7 A) .

3. Sealant according to any of the preceding embodi ments, wherein the zeolite is in powder form and has an average particle size of 1-60 pm, preferably 10-50 pm, more preferably 15-40 pm, such as 20-30 pm.

4. Sealant according to any of claims 1-3, wherein the zeolite is selected from CaA zeolites, CaX zeolites, NaX zeo lites, NaY zeolites, and a natural zeolite of Nickel-Strunz class 09. G.

5. Sealant according to any of claims 1-4, wherein the zeolite is grinded, milled, sieved, and combinations thereof.

6. Sealant according to any of claims 1-5, wherein the filler is selected from chalk, precipitated chalk, coated pre^¬ cipitated chalk, silica, carbon black, and combinations thereof.

7. Sealant according to any of claims 1-6, wherein the plasticizer is selected from benzoates, phthalates, tereph- thalates, polyols, hydrogenated versions of phthalates, tereph- thalates and benzoates, and combinations thereof.

8. Sealant according to any of claims 1-7, wherein the additives are selected from catalysts, co-catalysts, rheology control agents, pigments, pigment pastes, HALS, UV stabilizers, antioxidants, adhesion promotors, drying agents, and combinations thereof.

9. Sealant according to any of claims 1-8, wherein the polymer comprises a functionalized polyether backbone with meth- oxy silane terminal groups or ethoxy silane terminal groups, the modified silyl polymer comprises one or more -An-D-SiXYZ end groups wherein:

A is a divalent linking group comprising at least one hetero atom,

D is a divalent hydrocarbon residue with 1-12 C- atoms

X, Y, Z are each independently substituents on the Si atom, and are independently selected from Ci-Ce alkyl, Ci- CB alkoxy, Ci-Ce acyloxy, and wherein at least one of the substituents X, Y, Z is a Ci-Cs alkoxy or Ci-Cg acyloxy, and

n is 0 or 1,

10. Sealant according to claim 9, wherein A is selected from oxygen, -NR'-, amide, carbamate, urea, imino, carboxylate, carbamoyl, amidino, and carbonate, wherein R' =H or C1-C4 alkyl, preferably oxygen or -NH- .

11. Sealant according to any of claims 9-10, wherein D is selected from alkyl residues, such methyl, ethyl, and n-pro- pyl.

12. Sealant according to any of claims 1-11, wherein the silyl modified polymer is selected from at least one of MS-poly- mers, dimethoxy silyl terminated polyether, and trimethoxy silyl terminated polyether.

13. Sealant according to any of claims 1-12, wherein the booster comprises 30-80 wt.% silyl modified polymer or plasti cizer, and 1-15 wt.% water.

14. Kit of parts comprising at least one of a first component and a second component according to any of the claims 1- 13, wherein a ratio of first component : second component is 100:1 to 100:15 (wt./wt.).

15. Use of a sealant according to any of claims 1-13 for sealing or bonding joints for increased strength build- up, for adhering a workpiece, such as a car window, a car panel, for buildings, such as homes, sheds, factories, offices, and high- rise buildings, road-infrastructure, such as viaducts, bridges, and fly-overs, transport vehicles, such as cars, trucks, busses, trains, vans, motorhomes, caravans, and trailers, ships, such as yachts, ships, and boats, or for improving storage stability.