JPS61177217A - Manufacture of highly rigid molded body made of diacetylene group-containing polyurethane - Google Patents

Abstract

PURPOSE:To mold highly rigid molded part made of polyurethane containing diacetylene group, which is useful for a precision machinery component by a method wherein polyurethane containing diacetylene group, which has a unit represented by the specified formula and the molecular weight of which is 1X10<3>-1X10<5>, is molded under high pressure. CONSTITUTION:Polyurethane containing diacetylene group is molded in solid state under high pressure. The polyurethane containing diacetylene group is a polymer containing a unit represented by the formula indicated in the attached note and having the molecular weight of 1X10<3>-1X10<5>. Five hundred atmosphere and higher is enough and 1,000-8,000 atmosphere is preferable for the pressing pressure for molding. The melting temperature of the polyurethane containing diacetylene group or less is enough and the temperature ranging from the room temperature (20 deg.C) to 200 deg.C is preferable for the temperature during the pressure molding. the resultant highly rigid molded body of polyurethane containing diacetylene group is an extremely highly rigid molded body, the compression modulus of elasticity of which is 3GPa or higher or, in special case, 6GPa or higher and is excellent in denseness and high in hardness.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing a highly rigid diacetylene group-containing polyurethane molded body useful as precision mechanical parts such as gears and cams.

[Prior art]

It is well known that certain diacetylene compounds can be polymerized in the crystalline state by heat and high energy radiation such as gamma or ultraviolet radiation (topochemical bolimerization).

However, although there are some reports on polyurethanes containing diacetylene groups, there are few research examples (Mak
romo, Chem, -L14-, 219-22
9 (1970), Arm, Khim, Zh.
, 23(11).

1004-1009 (1970), USP 3,7
09.860 etc.). No attempt has yet been made to mold diacetylene group-containing polyurethane to obtain a highly rigid molded product.

The present inventors focused on the characteristics of the diacetylene structure, especially its high reactivity, and as a result of intensive research in order to take advantage of the high reactivity, the present inventors developed polyurethane containing a diacetylene structure in a solid state below its melting temperature. By molding under high-pressure conditions, we succeeded in obtaining a highly rigid molded body and arrived at the present invention.

That is, the present invention relates to a method for producing a highly rigid molded article, which is characterized by molding diacetylene group-containing polyurethane in a solid state under high pressure conditions.

The diacetylene group-containing polyurethane in the present invention is a polymer having a unit represented by the following general formula (1) and having a molecular weight of 1 x 103 to I x 10''.

In accordance with a conventional method, an organic diisocyanate, a diacetylene base, and a diol 2,4-hexadiyne-1,6
- Can be synthesized by addition reaction with diol.

Examples of organic diisocyanates include hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), 4,4'-diphenylmethane diisocyanate (MDI), 2.4- ) lylene diisocyanate 1- (2 , 4-TD I ), 2,6-tolylene diisocyaner) (2,6-TD I ), metaxylylene diisocyaner) (XDI), 1.5-naphthalene diisocyanate, 4.4'-dicyclohexyl This can be achieved by using a mixture of methanediisocyanate (hydrogenated MDI) and the like.

On the other hand, the comonomer 2,4-hexadiyne-1,6
-Diols can be synthesized by oxidative coupling of propargyl alcohol in a conventional manner.

Polyurethane can be synthesized by the polyaddition reaction of diisocyanate and diol by a conventional method for polyurethane production as described in books such as Plastic Materials Course [2] Polyurethane Resin (Nichiko Kogyo Shimbun).

The molecular weight of the diacetylene group-containing polyurethane is not particularly limited, but is generally between I x 103 and I x 105. Although there is no limit to the shape of the diacetylene group-containing polyurethane, a powdery shape is preferably used.

The method for producing a highly rigid molded body of diacetylene group-containing polyurethane of the present invention is characterized in that the diacetylene group-containing polyurethane produced by the above method is molded in a solid state under high pressure.

As a method for molding under high pressure, for example, a pressurization method such as a hydrostatic pressurization method can be used. The pressurizing pressure only needs to be 500 atm or more, and there is no particular upper limit.

Preferably it is 1,000 atm to 8,000 atm.

Also, when pressurizing, it is possible to mold by applying pressure under atmospheric pressure, but in order to obtain a molded body without voids, the air in the pressurized container and sample voids must be evacuated during pressurization, and the pressure must be reduced or vacuumed. It is preferable to perform pressure molding.

The temperature during pressure molding is not particularly limited as long as it is below the melting temperature of the diacetylene group-containing polyurethane. Preferably, the temperature may range from room temperature (20°C) to 200°C,
More preferably, the temperature is in the range of 50°C to 150°C. The reason for this is that diacetylene group-containing polyurethane is heated to about 160°C.
This is because an exothermic reaction occurs at about 200° C., so it is necessary to mold at a temperature below that temperature.

The highly rigid molded article of the diacetylene group-containing polyurethane of the present invention obtained in this manner can be prepared by adding an inorganic or organic photonic agent, a pigment, It is also possible to mold the product by adding ultraviolet absorbers, stabilizers, etc.

Next, the present invention will be illustrated in more detail with examples.

In the text, all parts are expressed in parts by weight. The examples do not limit the scope of the invention.

Reference Example 1 Production of diacetylene group-containing polyurethane 4-wheel drive unit with a capacity of 1 ton equipped with a stirring device, a dropping funnel, a nitrogen introduction pipe and a thermometer
2.4-Hexadiyne-1 under a nitrogen stream in a flask
, 6-diol (33 parts (0.3 mol)) was dissolved in 300 parts of dry N,N-dimethylformamide, and further 0.3 di-n-butyltin dilaurate was added as a urethanization catalyst.
and 5 parts of triethylamine were added.

Next, 505 parts of hexamethylene diisocyanate (0
, 3 mol) was added into the flask under stirring and allowed to react for 1 hour. Subsequently, the mixture was heated by external heating and reacted at □60°C for 3 hours.

After the reaction is complete, add 3000 parts of methanol (1000 parts) to the reaction solution.
The mixture was washed with 50% methanol and dried under reduced pressure for about 100 hours.

Product yield was 83 parts. This product is abbreviated as
It was confirmed that Further, as a result of molecular weight measurement using GPG (Kell permeation chromatography), the number average molecular weight was 3.6 x 10' (in terms of polystyrene).

The type of diisocyanate was changed in the same manner, and diacetylene group-containing polyurethane Po1y (IPDI/2.4-HD) was prepared from inphorone diisocyanate, Po1y (hydrogenated MDI/2. 4-HD
)Poly (MDI/2,4HD), TD from MDI
Po1y (TDI/2.4-HD) was produced from I, and Po1y1' (xDI/2.4-4D) was produced from XDI.

Reference Example 2' In place of 2,4-hexadiyne-1,6-diol in Reference Example 1, 1,6-hexanediol was used to prepare a polyurethane containing no acetylene group [poly(oxycarbonylimine-hexamethyleneimino)]. Pressure and pressurize the cuff.
960 Ai'/*1 Pressure molding was performed for 10 minutes. The obtained molded body was in the shape of a dark red disk with a thickness of about 2 m and a major axis of 20 cm.

The obtained molded body was cut into a rectangular parallelepiped with a height of 14 squares, a width of 13 mm, and a thickness of 2 cm, used as a test piece, and tested at a test speed of 0.5 w/min using an Autograph DSS-500 type (manufactured by Takasu Seisakusho). A compression test was conducted.

The compressive modulus of elasticity was 3.90 Pa, and the compressive strength was 98 Pa.

= 9 = Comparative Example 1 A molded article obtained by molding the acetylene group-free polyurethane (Poly(HMD I/, 1.6-HDO) produced in Reference Example 2 under the same conditions as Example 1) A compression test was conducted.The compression elastic modulus of the obtained molded product was 1.5G.
Pa, the intensity was changed to 29 MPa and a very weak time of 4 hours. The height of the obtained molded body is 13w11. Width 10
A test piece with a thickness of 1.8 m was cut out and subjected to a compression test. The compressive modulus of the obtained molded body was 6. I GPa and compressive strength were 99 MPa.

Example 4 Po1y (MDI/2.4-HD) was used instead of Po1y (HMDI/2.4-HD) in Example 1, and the pressure cuff '+6''O#/ca was pressurized for 2 hours. When molded, a similar molded product was obtained. When the resulting molded product was subjected to a compression test, the compression elastic modulus was 4.
．． The compressive strength was 8 GPa and the compressive strength was 120 MPa.

Example 5.6 Po1y of Example 1 (HMD I/2.4-H
D) instead of Po1y (IPDI/2.4-HD
) and Po1y (hydrogenated MDI/2.4-HD), a similar molded body was obtained.

Pol'y of Example 1 (HMD I/2.4-
Press and mold HD I with a mold including L, preheat at 130℃ for 5 minutes, press 6 pressure for 10 minutes at 4~s 90 #'/c:rl, thickness 4 spit, width.

[Brief explanation of drawings]

FIG. 1 is a half-cutaway sectional view of the molding device. In the figure, 1 is a push rod, 2 is a presser metal fitting, 3 is an outer cylinder, 4 is an inner cylinder, 5 is a base, 6 is an air exhaust pipe, 7 is a support rod, 8 is an O-ring holder, 9 is a mirror plate, 10 is above the O-ring, 11 is below the O-ring, and 12 is molding resin powder.

Claims (2)

[Claims] (1) Diacetylene group-containing polyurethane having a unit represented by the following general formula (1) and having a molecular weight of 1 x 10^3 to 1 x 10^5 is molded under high pressure. A method for producing a highly rigid molded article containing polyurethane. ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・(1) (In the formula, R is N of a diisocyanate having 2 to 20 carbon atoms.
This is the residue excluding CO. ) (2) When producing a highly rigid molded product of diacetylene group-containing polyurethane, the diacetylene group-containing polyurethane is in a solid state under a high pressure of 500 atm or more and room temperature or higher for 200 m
2. The method for producing a highly rigid molded article according to claim 1, wherein the molding is performed under conditions of 0° C. or lower.