JPH03223323A - Polyurethane resin composition and its production - Google Patents

Abstract

PURPOSE:To obtain a polyurethane resin composition improved in dispersion stability during nonaqueous suspension polymerization and that of a nonaqueous dispersion by mixing a urethane polymer obtained from a polyol and a polyisocyanate with a specified dispersion stabilizer. CONSTITUTION:A polyol (a) (e.g. polycaprolactonediol) is mixed with a polyisocyanate (b) (e.g. isophorone diisocyanate) and an active hydrogen- containing polysiloxane derivative (c) (e.g. polysiloxanediol having a hydroxyl group on each end) in such a mixing ratio that the ratio of component (b) to the total of components (a) and (c) is 1.2-0.8 in terms of an NCO to active hydrogen equivalent ratio, and the mixture is allowed to react to obtain a dispersion stabilizer (B) comprising a urethane polymer and used for polyurethane resin. A urethane polymer (A) obtained from components (a) and (b) is mixed with component B to obtain the title composition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a polyurethane resin composition useful as a paint or coating vehicle, and a method for producing it.

[Prior Art] Conventional techniques for producing non-aqueous dispersions and powders of polyurethane resins include using polyacrylates and polyesters as dispersion stabilizers. (For example, JP-A-49-52
(No. 295, and JP-A-48-169H) [Problems to be Solved by the Invention] However, these have the problem of poor dispersion stability during non-aqueous suspension polymerization and in non-aqueous dispersions.

[Means for Solving the Problems] The present inventors have arrived at the present invention as a result of intensive studies on polyurethane resins that have good dispersion stability and can be used to produce both non-aqueous dispersions and powders.

That is, the present invention provides polyol (a), polyisocyanate)
(b) and a dispersion stabilizer for a polyurethane resin consisting of a urethane polymer made from a polysiloxane derivative with active hydrogen bases; polyol (a) and polyisocyanate (b)
), (a) and (b) as dispersion stabilizers, and a urethane polymer (II) from a polysiloxane derivative in which the active hydrogen base is a polyurethane resin composition: A claim that the polyurethane resin composition is in powder form. Composition according to 1: from a non-polar solvent, a urethane polymer (I) from a polyol (a) and a polyisocyanate (b) and from (a), (b) as dispersion stabilizers and an active hydrogen-containing polysiloxane derivative A non-aqueous dispersion characterized by comprising a urethane polymer according to claim 1: A non-aqueous dispersion characterized by polymerizing polyol (a) and polyisocyanate (b) in a non-polar solvent in the presence of the dispersion stabilizer according to claim 1. A method for producing an aqueous dispersion, and polyol (a) and polyisocyanate (
This is a method for producing a powdered polyurethane resin, which is characterized by polymerizing b) and separating the nonpolar solvent.

Polyols (a) used in the present invention include polyether diols and polyester diols.

Examples of polyether diols include low molecular weight glycols [ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1.4-, 1.
3-butanediol, neopentyl glycol, l, 6
-hexanediol, l,8-octamethylene diol, alkyl dialkanolamine; low molecular weight diols having a cyclic group [e.g. those described in Japanese Patent Publication No. 45-1474: bis(hydroxymethyl)cyclohexane, entero- and p- xylylene glycol, bis(hydroxyethylbenzene, l,4-bis(2-hydroxyethoxy)benzene, 4,4'-bis(2-hydroxyethoxy)-diphenylpropane (ethylene oxide adduct of bisphenol A), etc.), and these alkylene oxides (alkylene oxides having 2 to 4 carbon atoms: ethylene oxide, propylene oxide,
1.2-12.3-11.3-butylene oxide, etc.)
adducts, and those obtained by ring-opening polymerization or ring-opening copolymerization (block and/or random) of alkylene oxides, cyclic ethers (such as tetrahydrofuran), such as polyethylene glycol, polypropylene glycol,
polyethylene-polypropylene (block and/or random) glycol, polytetramethylene ether glycol, polytetramethylene-ethylene (block and/or random) glycol, polytetramethylene-propylene (block and/or random) glycol,
Examples include polyhexamethylene ether glycol, polyoctamethylene ether glycol, and mixtures of two or more thereof.

Polyester diols include condensed polyester diols obtained by reacting low-molecular-weight diols and/or polyether diols with a molecular weight of 1000 or less with dicarboxylic acids, and polylactone diols obtained by ring-opening polymerization of lactones.

The low molecular weight diols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1.4-, 1.3-butanediol,
Neopentyl glycol, l,6-hexanediol,
l,8-octamethylene diol, alkyl dialkanolamine; low-molecular-weight diols having a cyclic group [e.g. those described in Japanese Patent Publication No. 1474/1983: bis(hydroxymethyl)cyclohexane, - and p-xylylene glycol, bis (Hydroxyethylbenzene, 1.4-bis(2-hydroxyethoxy)benzene, 4.4'-bis(2-hydroxyethoxy)-diphenylpropane (ethylene oxide adduct of bisphenol A), etc.), and two or more of these Mixtures may be mentioned. Molecular weight 100
Examples of the polyether diol of 0 or less include the aforementioned polyether diols such as polyethylene glycol, polytetramethylene ether glycol, polypropylene glycol, triethylene glycol; and mixtures of two or more thereof. In addition, dicarboxylic acids include aliphatic dicarboxylic acids (succinic acid, adipic acid, sebacic acid,
Examples of the lactone include glutaric acid, azelaic acid, maleic acid, fumaric acid, etc.), aromatic dicarboxylic acids (terephthalic acid, isophthalic acid, etc.), and mixtures of two or more thereof; and the lactone includes ε-caprolactone.

Polyester diols can be prepared using conventional methods, such as adding low molecular weight diols and/or polyether diols with a molecular weight of 1000 or less to dicarboxylic acids or their ester-forming derivatives [e.g. anhydrides (maleic anhydride, phthalic anhydride, etc.), lower esters (terephthalic anhydride, etc.)]. dimethyl acid, etc.), halides, etc., or their anhydrides and alkylene oxides (e.g., ethylene oxide and/or propylene oxide), or initiators (low molecular diols and/or polyethers with a molecular weight of 1000 or less). It can be produced by adding lactone to diol).

Specific examples of these polyester diols include polyethylene adipate, polybutylene adipate, polyhexamethylene adipate, polyneopentyl adipate, polyethylene propylene adipate, polyethylene butylene adipate, polybutylene hexamethylene adipate, polydiethylene adipate, and poly(polyethylene adipate). tetramethylene ether) adipate, polyethylene azelate, polyethylene sebacate, polybutylene azelate,
Examples include polybutylene sebacate, polycaprolactone diol; and mixtures of two or more thereof.

The average molecular weight (by hydroxyl value measurement) of these polymeric diols is usually 500 to 500G, preferably 700 to 500G.
It is 4000.

The polyisocyanate (b) used in the present invention includes aliphatic polyisocyanates having 2 to 12 carbon atoms (excluding carbon in the lICO group), alicyclic polyisocyanates having 4 to 15 carbon atoms, and 8 to 12 carbon atoms. Aroaliphatic polyisocyanates, aromatic polyisocyanates having from B to 20 carbon atoms, and modified products of these polyisocyanates (containing carposiimide groups, uretdione groups, uretdione groups, urea groups, biuret groups and/or incyanurate groups) modified products, etc.) can be used. Such polyisocyanates include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (DI), dodecamethylene diisocyanate,
1.8.11-Undecane triisocyanate, 2,2
．． 4-) Limethylhexane diisocyanate, lysine diisocyanate, 2,6-diycyanate methyl caproate, bis(2-incyanate ethyl) fumarate, bis(2-incyanate ethyl) carbonate,
2-Incyanatoethyl-2,8-diisocyanatehexanoate; Isophorone diisocyanate) (I
PDI), dicyclohexylmethane diisocyanate) (
D in water ffi, cyclohexylene diisocyanate,
Methylcyclohexylene diisocyanate (1 TDI of water)
), bis(2-incyanatoethyl) 4-cyclohexene-1,2-dicarboxylate;
Water-modified products of 01, trimerized products of IPDI, etc.; tolylene diisocyanate (TDI), crude TDI, diphenylmethane diisocyanate (MDI), polyphenylmethane polyisocyanate (crude 1101), modified 101 (carposiimide-modified IDI, etc.), naphthi and mixtures of two or more thereof. Among these, aliphatic diisocyanates and alicyclic diisocyanates are preferred in terms of resistance to cracking of the coating film, and particularly preferred are hexamethylene diisocyanate and isophorone diisocyanate.

In the active hydrogen-containing polysiloxane derivative used in the present invention, the active hydrogen is OH.

Examples include NHa, COOH or SH. The number of active hydrogens is usually 1 to 3, preferably 2. Examples of active hydrogen-containing polysiloxane derivatives include compounds represented by general formula (1).

K reference K4 (R+, R2, R co, R4 is 0cH3, CpH2en,
CHa) k-X, -CsHsOQ-(OH)-1
-CHmCH(CHa)CsHsl -(CHt)
*O(C*H40), (CsHsO)bRs,
-(CHI)2NHCHa CH2N Hm.
: However, at least one of R+, Rs, Ra, and R4 is an active hydrogen group. : p is 1 to 22, q is 1
-5 is an integer, alb is an integer from 1 to 40. k
is 2 or 3, mr n is an integer greater than or equal to 0, and mrn is 1
~350. :(Q) is a polyhydric alcohol residue, R
6 is H, CHs, QCHs. X is OH=
N Ha-COOH or SH. ) Specific examples of these compounds include the following.

CH, CH.

CH2CH2CHHO2(Cm HaO) + s (
Cs Hs O) t a OCIIm where n' is 1 to 2
50, p' is 1 to 250, q' is an integer from 1 to 4, and p
'+q' has a value of 1 to 350.

Among these, preferred are polysiloxane derivatives containing terminal hydroxyl groups and polysiloxane derivatives containing terminal amino groups, and particularly preferred are polysiloxane derivatives containing terminal hydroxyl groups. The molecular weight is usually 500 from the viewpoint of dispersibility.
~30,000, preferably 1,0Go-10,000
It is.

Polyol (a) in a nonpolar solvent in the presence of the above dispersion stabilizer
A non-aqueous dispersion can be produced by polymerizing and polyisocyanate (b).

Non-polar solvents used in the present invention include aliphatic, cycloaliphatic, and aromatic hydrocarbons.

Examples of aliphatic and alicyclic hydrocarbons include n-hexane,
Examples of aromatic hydrocarbons include n-hebutane, n-octane, isooctane, petroleum benzene, ligroin, mineral spirits, cyclohexane, kerosene, petroleum naphtha, and the like, toluene, xylene, ethylbenzene, and isopropylbenzene. Among these, aliphatic and alicyclic hydrocarbons are preferred from the viewpoint of stability of the dispersion.

In the present invention, when producing urethane polymer (I) from polyol (a) and polyisocyanate (b), the ratio of polyol (a) to polyisocyanate (b) is usually 1.5 to 2.5, Preferably 1.8
~2.

Polyol (a) as a dispersion stabilizer according to the present invention,
When producing a urethane polymer from polyisocyanate (b) and an active hydrogen-containing polysiloxane derivative, the ratio of polyol (a) and active hydrogen-containing polysiloxane derivative to polyisocyanate is such that the NGO/active hydrogen equivalent is usually 1.2 to 0. .8, preferably 1.1 to 0.9.

The dispersion stabilizer is prepared in advance and added when reacting polyol (a) and polyisocyanate (b) in a nonpolar solvent to produce a nonaqueous dispersion.

During the production of the urethane polymer and dispersion stabilizer in the present invention, the reaction temperature may be the same as the temperature normally employed when performing urethanization in the industry, and is usually 20°C to 15°C.
The temperature is 0°C, preferably 50°C to 120°C. In order to accelerate the reaction, amine catalysts (triethylamine, N-ethylmorpholine, triethylenediamine, etc.) and tin-based catalysts (trimethyltin laurate, dibutyltin dilaurate, etc.) used in normal urethane reactions may be used. . Furthermore, if necessary, a polymerization terminator such as a monohydric alcohol (methanol, butanol, cyclohexanol, etc.), a monohydric amine (methylamine, dimethylamine, butylamine, cyclohexylamine, etc.), etc. can also be used.

The reaction apparatus for producing the urethane polymer dispersion stabilizer non-aqueous dispersion and powder in the present invention can be a production apparatus normally employed in the industry.

Polyol (a) and polyisocyanate in the present invention)
The amount of urethane polymer (I) from (b) is usually 30 to 60%, preferably 35 to 55%, based on the weight of the non-aqueous dispersion. Urethane polymer (I) is BO
If it exceeds X, the viscosity of the dispersion will increase rapidly and the sprayability as a coating agent will deteriorate. If it is less than 30%, dispersion stability deteriorates.

The urethane polymer (II) from the active hydrogen-containing polysiloxane derivative, polyol (a) and polyisocyanate (b) as a dispersion stabilizer is
Based on the amount of 1), it is usually 0.1 to 20%, preferably 0.5 to 15%. If the amount of the dispersion stabilizer exceeds 20%, the viscosity of the dispersion will increase rapidly, resulting in poor sprayability as a coating agent, and if the amount is less than 0.1%, the dispersibility will be poor.

The amount of non-polar solvent is usually 40 to 70%, preferably 45 to 65%, based on the amount of urethane polymer (I). If the nonpolar solvent exceeds 70%, dispersion stability will deteriorate. If it is less than 40%, the viscosity of the dispersion becomes high and the sprayability as a coating agent deteriorates.

Polyol (
A powdered polyurethane resin composition can be produced by polymerizing a) and polyisocyanate (b) and separating the nonpolar solvent.

In the production of powder in the present invention, after producing the above-mentioned non-aqueous dispersion,
It can be obtained by removing the dispersion medium by a known method such as filtration, centrifugation, or decantation. After separation, the powder can be dried on a tray, on a wire mesh, or on a fluidized bed.

The non-aqueous dispersion and powder of the present invention can be used as paints (for example, magnetic paints) and coating vehicles. These non-aqueous dispersions and powders are supplemented with auxiliary additives, such as coloring agents such as dyes and pigments for decorative coloring, inorganic fillers such as calcium carbonate and glass fiber, and additives to improve heat resistance and heat deterioration resistance. Various stabilizers, softeners, plasticizers, and isocyanate-based crosslinking agents for improving strength, such as 1 mole of hatrimethylolpropane and 3 moles of 1,6-hexamethylene diisocyanate, tolylene diisocyanate, or inphorone diisocyanate. Examples include adducts synthesized from

[Example] The present invention will be further explained below with reference to Examples, but the present invention is not limited thereto. Parts in the examples are parts by weight.

Production Example 1 In a three-necked flask equipped with a stirrer, a reflux condenser, and a nitrogen blowing tube, 500 parts of toluene, 355.3 parts of a polysiloxane diol containing hydroxyl groups at both ends (KF6003; manufactured by Shin-Etsu Silicone) with a molecular weight of s and ooo, and a molecular weight of 2. 000 polycaprolactone diol, 2G, 3 parts of isophorone diisocyanate) were charged, heated to 100°C and reacted for 8 hours to obtain a molecular weight of 11,000. A urethane polymer as a dispersion stabilizer having a solid content of 50×1 and a viscosity of 1500 cps/25° C. was obtained (this will be referred to as S-1).

Production Example 2 Polytetramethylene glycol 11 with a molecular weight of 2,000
2.5 parts, polysiloxane diol containing hydroxyl groups at both ends with a molecular weight of 2.000 (KF6001; manufactured by Shin-Etsu Silicone)
337.5 parts and 50.0 parts of inphorone diisocyanate) were prepared in the same manner as in Production Example 1, with a molecular weight of approximately 13.
,000. Solid content 50x1 Viscosity 1800cps
A urethane polymer was obtained as a dispersion stabilizer at /25°C (this will be referred to as S-2).

Production Example 3 Polytetramethylene glycol l1 with molecular weight 2.000
8.4 parts, polysiloxane diol containing a hydroxyl group at one end (
X-22-178D; Shin-Etsu Silicone) II8.4
A urethane polymer as a dispersion stabilizer having a molecular weight of about 12.0001, a solid content of 50%, and a viscosity of 2.100 cps/25°C was obtained in the same manner as in Production Example 1 except that 26.3 parts of inphorone diisocyanate was used. This is S-3
).

Example 1 In a four-hole flask equipped with a stirrer, a reflux condenser, a nitrogen blowing tube, and a dropping funnel, 600 parts of n-hebutane and 150 parts of the stabilizer S- from Production Example 1 were charged and dissolved under stirring. Then, while stirring, 4 parts of polycaprolactone diol having a molecular weight of 2,000, 4 parts, and 30 parts of 1,4-butanediol were added.
6 parts and 123.1 parts of isophorone diisocyanate were added dropwise and dispersed. Further, it was reacted for 4 hours at 85℃, average particle diameter was 2μ, viscosity was 130cps/25℃, and solid content was 40″A.
The resulting non-aqueous dispersion H-1 was stable without separation and sedimentation even after 3 months. H-1 was spray-coated on a glass plate to a dry film thickness of 10 Gμ, air-dried at 25°C for 3 days, and the physical properties of the film were measured. 100% stress t40
kg/am', 300% stress; 150kg/c/1
Breaking strength: 150 kg/CI2, elongation: 400%.

Example 2 Except for using 1000 parts of the stabilizer S-2 of Production Example 2, 261.9 parts of polytetramethylene glycol with a molecular weight of 2,000, 32.5 parts of ethylene glycol, and 105.8 parts of hexamethylene diisocyanate). In the same manner as in Example 2, the average particle size was 2 μ, the viscosity was 125 cps/25°C, and the solid content was 4.
A 0% non-aqueous dispersion was obtained (this will be referred to as H-2).

The obtained non-aqueous dispersion H-2 remained stable without separation and precipitation even after 3 months. The physical properties of the film measured in the same manner as in Example 1 were: 100X stress;
, 300% stress; 80 kg/cI12, breaking strength; l
The weight was 750%, and the elongation was 750%.

Example 3 350 parts of the stabilizer S from Production Example 3, 268 parts of polytetramethylene glycol with a molecular weight of 2.1)00, 36.2 parts of 1,4-butanediol, xylylene diisocyanate)9
A non-aqueous dispersion having an average particle diameter of 2 μ, a viscosity of 12 Scps/25° C., and a solid content of 40% was obtained in the same manner as in Example 1, except that 5.8 parts were used (this will be referred to as H-3).

The obtained non-aqueous dispersion H-3 remained stable without separation and precipitation even after 3 months. The physical properties of the film measured in the same manner as in Example 1 were: 100% stress; 30 kg/cm";
300% stress: 100kg/cI12, breaking strength 125
0 kg/al12, elongation: 5 sox.

Example 4 The same procedure was used as in Example 1 except that the amount of stabilizer S-t used in Example 1 was changed to 5 parts, and the particle size was 10-150μ and the viscosity was 125c.
A non-aqueous dispersion with a solid content of 40% was obtained at ps/25°C. This was filtered through a 200-mesh wire mesh and dried for 1 hour in a circulating dryer at 50°C to obtain a powdered polyurethane resin composition with a particle size of 50 to 250 μm (this will be referred to as P-2).

Example 5 The same procedure was used as in Example 2 except that the amount of stabilizer S-2 was changed to 5 parts.
A non-aqueous dispersion with a solid content of 40% was obtained at ps/25°C. This was filtered through a 200-mesh wire mesh and dried for 1 hour in a circulating dryer at 50°C to obtain a powdered polyurethane resin composition with a particle size of 50 to 250 μm (this will be referred to as P-2).

Example 6 A product was prepared in the same manner as in Example 3, except that the amount of stabilizer S-3 was changed to 3 parts.
A non-aqueous dispersion with a solid content of 40% was obtained at ps/25°C. This was filtered through a 200-mesh wire mesh and dried for 1 hour in a dryer at 50° C. to obtain a powdered polyurethane resin with a particle size of 50 to 250 μm (this will be referred to as P-3).

Comparative Example 1 In Example 1, an acrylic polymer with a molecular weight of about 17,000 (lauryl methacrylate/glycidyl methacrylate copolymer; copolymerization ratio = 9515) was used as a stabilizer.
A non-aqueous dispersion was obtained in the same manner as in Example 1 except that 0 part was used. This product was separated and sedimented after 3 days. Furthermore, when the obtained non-aqueous dispersion was powdered in the same manner as in Example 4, the particles agglomerated.

Comparative Example 2 A non-aqueous dispersion was obtained in the same manner as in Example 1 except that 50 parts of a soybean oil-modified alkyd resin with an oil length of 40% was used as a stabilizer. This product was separated and sedimented after 3 days. Further, the obtained non-aqueous dispersion was powdered in the same manner as in Example 4, but the particles agglomerated.

[Effects of the Invention] The polyurethane resin composition, nonaqueous dispersion, powdered polyurethane resin composition, and method for producing the same obtained by the present invention have the following effects.

1. Improved dispersion stability.

Claims (1)

[Claims] 1. A dispersion stabilizer for polyurethane resins comprising a urethane polymer made from a polyol (a), a polyisocyanate (b) and an active hydrogen-containing polysiloxane derivative. 2. Polyol (a) and polyisocyanate (b)
1. A polyurethane resin composition comprising a urethane polymer (I) from , as well as (a) and (b) as dispersion stabilizers, and a urethane polymer (II) from an active hydrogen-containing polysiloxane derivative. 3. The composition according to claim 2, which is in powder form. 3. Urethane polymer (I) from a non-polar solvent, polyol (a) and polyisocyanate (b) and urethane polymer (II) from (a), (b) as a dispersion stabilizer and an active hydrogen-containing polysiloxane derivative ) A non-aqueous dispersion characterized by comprising: 4. A method for producing a non-aqueous dispersion, which comprises polymerizing polyol (a) and polyisocyanate (b) in a nonpolar solvent in the presence of the dispersion stabilizer according to claim 1. 5. A powdered polyurethane resin composition, characterized in that polyol (a) and polyisocyanate (b) are polymerized in a nonpolar solvent in the presence of the dispersion stabilizer according to claim 1, and the nonpolar solvent is separated. Manufacturing method.