JPH03140318A - Polyurethane and production thereof - Google Patents

Abstract

PURPOSE:To obtain the title polymer excellent in low-temperature resistance, mechanical properties, resistance to oil and wear, etc., by polymerization be tween a polycarbonate diol having specific structural unit and an isocyanate. CONSTITUTION:The objective polymer can be obtained by polymerization be tween (A) a polycarbonate diol 800-4000 in number-average molecular weight made up of unit(s) of formula I and/or II and units of formula III and IV, respec tively, with the sum of each molar fraction of the units I to III equal to that of the unit IV and the molar fraction of the unit III accounting for 5-30% of the sum of each molar fraction of the units I to III and (B) a diisocyanate (pref. 4,4'-diphenylmethane diisocyanate), in the presence of, if needed, a chain extender. For the present polymer, the main chain is made up of the units of the component A and unit of formula V (R is divalent saturated aliphatic hydrocarbon, saturated alicyclic hydrocarbon, etc.).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a novel polycarbonate polyurethane and a method for producing the same.

The polycarbonate polyurethane provided by the present invention has excellent cold resistance and mechanical performance.

[Conventional technology]

Polyurethane has long been attracting attention as an alternative material to rubber and plastic because it has many features such as high elastic modulus, excellent abrasion resistance and oil resistance, and 1 normal plastic molding methods can be applied to it. It has come to be used in large quantities as a molding material in a wide range of applications.

Polyurethane is produced by mixing and polymerizing polymeric diols, diincyanates, and chain extenders such as 1,4-butanediol. It is known that in order to produce homogeneous polyunthane, it is preferable to mix the raw materials in a molten state and polymerize.

Known polyurethanes include polyester polyurethane, polyether polyurethane, and polycarbonate polyurethane, and these polyurethanes are used for various purposes depending on their characteristics. For example, polyether polyurethane is used for applications where hydrolysis resistance is particularly required, and polyester polyurethane is used for applications where mechanical performance, oil resistance, and abrasion resistance are particularly required.

Furthermore, polycarbonate polyurethane is used in applications that require durability in addition to the features of polyester polyurethane.

[Problem to be solved by the invention]

Conventional polycarbonate-based polyurethanes have problems such as poor cold resistance, ie, low-temperature flexibility, and improvements are desired.

One object of the present invention is to provide a polycarbonate polyurethane having excellent cold resistance and excellent mechanical performance.

Another object of the present invention is to provide a method for producing the above polycarbonate polyurethane.

[Means for solving problems]

According to the present invention, the above object is achieved in that the main chain is substantially composed of polycarbonate diol units and the following structural units (V), and the polycarbonate diol units are substantially composed of the following structural units (I) and /It also consists of Fi(It) and structural units (III) and (IV), and the sum of the molar fractions of structural unit (I) or l[[) is the structural unit (I
V) substantially equal to the mole fraction of the structural unit (if
The mole fraction of f) is in the range of 5 to 30% with respect to the sum of the mole fractions of the structural units (r) to In).

This is achieved by providing a polyurethane with a logarithmic viscosity of 0.4 to 2.0 dt/f, which is substantially as described below. +1
Structural unit (I) and/mano (It) and structural unit (II)
I) and (IV), the sum of the mole fractions of structural units (I) to (III) is substantially equal to the mole fraction of structural unit (IV), and the mole fraction of structural unit (III) Number-average molecules [800 to 4,0
This is achieved by providing a method for producing the above polyurethane, which is characterized in that 000 polycarbonate diol and diisocyanate are polymerized in the presence or absence of a chain extender.

(I) : -0+Q(z'+IJo -CH3 (I[) : -0-Q(z-CH2CH2%0-(I
II): -0-Oh4)CHz-0-(IV)
: -c- (In the formula, R represents a divalent saturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group, or an aromatic hydrocarbon group.) The above structural unit will be explained in detail. The structural unit fl) is f
lJ, t is derived from 1,9-nonanediol.

Structural unit (II) is derived, for example, from 2-methyl-1,8-octanediol, and structural unit (III), for example, is derived from 1,4-cyclohexanedimetatool. Structural units (I) to (III) constituting the uninvented polyurethane are structural units ([[[] in which the molar fraction of the structural units (I) to (III) is 5 to Must be in the range of 30. Structural unit (III)
If the molar fraction is less than 5s, the resulting polyurethane will have poor mechanical properties, and if it exceeds 30 cm, the resulting polyurethane will have poor cold resistance.

Structural unit (IV) #i Structural unit (I) to (III
) is combined with carbonate bond. This structural unit is usually represented by the following general formula (■) X-0-C-0-X (y) (wherein, The compound is preferably derived from phosgene, but is preferably derived from caradiphenyl carbonate due to ease of preparation. In the polyurethane of the present invention, the molar fraction of the structural unit (V) is substantially equal to the sum of the molar fractions of the structural units (I) to [).

The aliphatic and alicyclic structural units (V) containing two isocyanate groups in the molecule are derived from aromatic diincyanates. Examples of diisocyanates include 1, 4,4'-diphenylmethane 7'/7f-), l
)-naphthylene diisocyanate, tolylene diisocyanate), 1,5-naphthylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, inphorone diincyanate, 4,4'-dicyclohexylmethane Examples include diisocyanate. As the diisocyanate, 4,4'-diphenylmethane diisocyanate is preferably used. It is also possible to use a small amount of trimethylolpropane or triisocyanate, which is obtained by adding 3 moles of diisocyanate to 1 mole of glycerin. As mentioned above, the polyurethane of the present invention is composed of polycarbonate diol and structural unit (V). It is produced by polymerizing a diisocyanate giving 7t+ in the presence of a chain extender or in the absence of 7t+. The polymerization conditions are those employed in known urethane production reactions.

As the chain extender, a chain extender commonly used in the Bo II urethane industry, ie, a low molecular weight compound having a molecular weight of 400 or less and containing at least two hydrogen atoms capable of reacting with incyanate, can be used.

Example Eva ethylene glycol, propylene gel■ 1 col,
1.4-butanediol, neopentyl glycol, l
, 6-hexanediol, 3-methyl-1゜5-pentanol, 1.4-cyclohexanediol, 1.4
-bis(β-hydroxyethoxy)benzene, bis(β-hydroxyethoxy)benzene, bis(β-hydroxyethoxy)benzene,
Diols such as -hydroxyethyl) terephthalate and quinrylene glycol; water; ethylene diamine, propylene diamine.

Diamines such as xylylene diamine, inphorone diamine, piperazine, phenylene diamine, and tolylene diamine; hydrazine; hydrazide such as adipic acid dihydrazide and inphthalic acid dihydrazide;

As a chain extender, 1,4-butanediol is 1.4
-Bis(β-hydroxyethoxy)benzene is most preferably used. These compounds may be used alone or in combination of two or more.

The polycarbonate diol used as a raw material for the polyurethane of the present invention consists essentially of the structural units (I) to (2) as described above. Polycarbonate diol is 1
For example, dephenolation reaction from a mixture of diphenyl carbonate, dicarboxylic acid nodiphenyl ester and diol,
Dealcoholization reactions from mixtures of carbonic acid dialkyl esters and dialkyl esters of dicarboxylic acids and diols, dehydrochlorination reactions from mixtures of phosgene and dicarboxylic acid chlorides and diols, mixtures of phosgene and alkali metal salts of dicarboxylic acid chlorides and diols It is produced by carrying out a reaction such as a dealkali metal chloride reaction from , if necessary, in the presence of a suitable catalyst. As the raw material for the polyurethane of the present invention, polycarbonate diol having a number average molecular weight determined from the hydroxyl value in the range of 800 to 4,0000 is used. If the number average molecular weight of the polycarbonate diol is less than 800, the resulting polyurethane will have poor low temperature properties such as cold resistance.

Moreover, when it is larger than 4,000, the mechanical performance of the resulting polyurethane is poor.

The polyurethane obtained as described above has a concentration of 0.5
3 as a dimethylformamide solution at f/100 d
It has a logarithmic viscosity of 0.4 to 2.0 dt/f determined at 0°C. Logarithmic viscosity of polyurethane is 0.5 to 1.5 dt/
f is preferred.

The polyurethane of the present invention can be easily molded using commonly used injection molding machines, extrusion molding machines, blow molding machines, and the like. The polyurethane of the present invention has excellent cold resistance and mechanical performance, so it can be used in sheets, films, rolls, gears, and solid tires.

Belts, hoses, tubes, backing materials, m-proof materials,
It is used as a material for shoe soles, sports shoes, and various other laminate products, as well as mechanical parts, automobile parts, sporting goods, and elastic fibers. The polyurethane produced by Mano Ippon @ Akira is dissolved in a solvent and used for artificial leather, fiber treatment agents, adhesives, binders, paints, etc. Note: The polyurethane of the present invention may be mixed with known fillers, stabilizers, colorants, reinforcing agents, etc., depending on the purpose.

[Examples] Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples in any way. In the Examples and Comparative Examples, the number average molecular weight of the polycarbonate diol and the logarithmic viscosity of the polyurethane were determined according to the following method. The cold resistance and mechanical performance of Manen polyurethane were evaluated according to the following method.

(I) Number average molecule 1: Determined from the hydroxyl value of polycarbonate diol as follows.

(2) Nff viscosity: Polyurethane was dissolved in dimethylformamide at a concentration of 0.5f/1QQt/ at 30°C.
It was measured with

(8) Cold resistance = A test piece made from a polyurethane film with a thickness of 100 μm was measured using a dynamic viscoelasticity measuring device [DYE Rheo Spectra manufactured by Rheology] by temperature dispersion to determine Tα (peak temperature of E', 11 Hz) to evaluate cold resistance.

(4) Mechanical performance: The strength at 100% elongation and the strength at 300% elongation were measured according to the test method for polyurethane thermoplastic elastomers specified in JIS K7311-1987.

Reference example 1 2-methyl-1,8-octanediol under nitrogen stream,
Molar ratio of 1,9-nonanediol and 1,4-cyclohexane dimetatool 3 (lj 60:10 mixture 1
, 721F and diphenyl carbonate 2,14 Of was heated and phenol was distilled off from the reaction system at 200°C. Gradually raise the temperature to 210-220℃,
After most of the phenol had been distilled off, the pressure was reduced to 6 to 10
The remaining phenol was completely distilled off at 210 to 220° C. under reduced pressure.

The polycarbonate diol thus obtained had a hydroxyl value of 56 and a number average molecular weight of 2,000.

Reference Examples 2 to 8 Production of Polycarbonate Diols The reactions were carried out in the same manner as in Reference Example 1 except that the diols giving the diol components shown in Table 1 were used to obtain the polycarbonate diols shown in Table 1, respectively.

Regarding the fL polycarbonate diols obtained in Reference Examples 1 to 8, the diol components, their ratios, and number average molecular weights are summarized in Table 1. In addition, in Table 1, diol components are indicated using the following abbreviations.

ND: l,9-nonanediol MOD: 2-methyl-1,8-octanediol CHD
M: l 4-Cyclohexane dimetatool HD
:1,6-hexanediol Table 1 1 A 60 30 10
2,0002 B 50 25
25 2,0003 C40
35252,0004D 85 1
5 2.1005 F 75
25 2.0006
F 20 80 2.0
007 G 40 20 40
2,0008 H65352,000 Example 1 Production and performance evaluation of polyurethane A mixture of polycarbonate diol (A) and 1,4-butanediol (hereinafter abbreviated as BD) heated to 30°C and 50°C Heat and melt to 7t 4.4
'-diphenylmethane diincyanate (hereinafter abbreviated as MDI) is rotated in the same direction with a metering pump in an amount such that the molar ratio of polycarbonate diol to MDI to BD is 1:3.0:2.0. The mixture was continuously charged into a twin-screw extruder and a continuous melt polymerization reaction was performed. The interior of this twin-screw extruder is divided into three zones: front, middle, and rear, with the temperature (polymerization temperature) of the middle section being the highest at 220°C. The produced polyurethane is continuously extruded into water in the form of strands, and then cut with a pelletizer and formed into pellets. Furthermore, sheets and films were obtained by molding pellets by hot pressing, and the cold resistance and mechanical performance of these K were evaluated. The evaluation results are shown in Table 2.

The obtained polyurethane had good cold resistance and mechanical performance.

Examples 2 to 5 and Comparative Examples 1 to 3 Polyurethane production and performance evaluation In Example 1, the polycarbonate diol shown in Table 2 was used instead of polycarbonate diol (A), and the polycarbonate diol, MDI, and BD were shown in Table 2. Cypolyurethane pellets were obtained by performing the reaction and operation in the same manner except that the molar ratio was the same, and the pellets were similarly molded into sheets and films, and various performances were evaluated. The evaluation results are shown in Table 2.

The polyurethanes obtained in Examples 2 to 5 are cold resistant.

Both mechanical properties were good.

The polyurethanes obtained in Comparative Examples 1 to 3 had poor cold resistance and mechanical performance.

Margins below [Effects of the Invention] As is clear from Table 2 above, the polycarbonate polyurethane provided by the present invention has excellent cold resistance and mechanical performance. 7) The polyurethane is oil resistant.
It also has excellent wear resistance. According to the present invention, a method for producing a polycarbonate polyurethane having such excellent properties is provided.

Special applicant: RiRashi Co., Ltd.

Claims (1)

[Claims] 1. The main chain is substantially composed of polycarbonate diol units and the following structural units (V), and the polycarbonate diol units are substantially composed of the following structural units (I) and/or ( II) and structural units (III) and (IV), the sum of the mole fractions of the structural units (I) to (III) is substantially equal to the mole fraction of the structural unit (IV), and the structural unit The molar fraction of (III) is the structural unit (I) or (
Polyurethane with a logarithmic viscosity of 0.4 to 2.0 dl/g in the range of 5 to 30% relative to the sum of the molar fractions of III). (I): ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II): ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (III): ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (IV): ▲ Mathematical formulas, chemical formulas , tables, etc. ▼ (V): ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R represents a divalent saturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group, or an aromatic hydrocarbon group. 2. The polyurethane according to claim 1, wherein the main chain is composed of the above polycarbonate diol unit and structural unit (V) and a structural unit derived from a chain extender. 3. Substantially the following structural units (I) and/or (
The sum of the molar fractions of the structural units (I) to (III) is the structural unit (II) and the structural units (III) and (IV).
IV) and the structural unit (III
) has a number average molecular weight 8 in which the molar fraction of structural units (I) to (III) is in the range of 5 to 30% of the sum of the molar fractions of structural units (I) to (III).
2. The method for producing polyurethane according to claim 1, wherein the polycarbonate diol having a polycarbonate diol of 0 to 4,0000 and a diisocyanate are polymerized in the presence or absence of a chain extender. (I): ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II): ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (III): ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II): ▲ Mathematical formulas, chemical formulas There are tables, etc.▼