CN108976406A - A kind of chlorinated polyether dihydric alcohol and its synthetic method - Google Patents

Abstract

The invention discloses a chlorinated polyether diol and a synthesis method thereof. The structural formula of the chlorinated polyether diol is shown in (I), and the synthesis process comprises the following steps: using 1,4-butanediol as a trigger agent, 3-chloromethyl-3-methyloxetane as a monomer to obtain chlorinated polyether diol through cationic ring-opening polymerization. The synthesis method is simple, and the terminal hydroxyl groups of the chlorinated polyether diol are all primary hydroxyl groups with high reactivity, which can endow the polyurethane elastomer with high mechanical properties. Wherein, x+y=8-60, which is an integer.

Description

A kind of chlorinated polyether glycol and its synthetic method

technical field

The invention relates to a chlorinated polyether diol and a synthesis method thereof. The compound can be used as a raw material of a polyurethane elastomer and belongs to the technical field of polymer materials.

Background technique

Chlorinated polyether polyol is a commonly used raw material in the polyurethane industry. The polyurethane elastomer prepared from it has the characteristics of flame retardancy, oil resistance, seawater resistance, and high bonding strength. It is widely used in special environments such as oil fields and oceans. In addition, chlorinated polyether polyols can also be used to synthesize other new graft polyethers and functional group-substituted polyethers, for example, chlorine atoms are replaced by azido groups to prepare azide polyether adhesives. Among them, polyepichlorohydrin polyol (PECH) is a typical representative, such as Guo Fengchun et al. "Research on Some Properties of Hydroxyl-terminated Polyepichlorohydrin Polyurethane", Polymer Materials Science and Engineering, 1988, 5: 74-77 The structure of polyepichlorohydrin polyol (PECH) and the mechanical properties of polyurethane are disclosed, and the structural formula of PECH is as follows:

Most of the hydroxyl groups at the end of the PECH molecular chain are secondary hydroxyl groups, which have low activity when reacting with isocyanate curing agents; and when the r value is 1.2, the mechanical properties of the prepared PECH polyurethane are: tensile strength is 3.43MPa, elongation is 375 %, there is a shortage of low mechanical properties.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies of the background technology and provide a chlorinated polyether diol capable of imparting higher mechanical properties to polyurethane elastomers and a synthesis method thereof.

The concept of the present invention is: 3-chloromethyl-3-methyloxetane monomer 3-chloromethyl-3-methyloxetane, which is disubstituted at the 3,3-position, undergoes cationic ring-opening polymerization to obtain a terminal group of Chlorinated polyether diols with primary hydroxyl groups have a certain symmetry in their molecular chains, which can endow polyurethane elastomers with higher mechanical properties.

In order to solve the problems of the technologies described above, the chlorinated polyether glycol of the present invention has a structural formula as follows:

Wherein, x+y=8-60, which is an integer.

Chlorinated polyether glycol synthetic route of the present invention is as follows:

Wherein, x+y=8-60, which is an integer.

Chlorinated polyether glycol synthetic method of the present invention, comprises the following steps:

Add 1,2-dichloroethane, 1,4-butanediol and boron trifluoride tetrahydrofuran complex in sequence to a four-neck round bottom flask equipped with mechanical stirring, reflux condenser, thermometer and dropping funnel , after stirring at a temperature of 20°C to 30°C for 30 minutes, start to add 3-chloromethyl-3-methyloxetane dropwise, the dropwise addition time is 1h~8h, and continue to react for 24h~48h after the dropwise addition is completed , neutralized with Na ₂ CO ₃ aqueous solution, washed the organic phase with water until neutral, and concentrated to obtain chlorinated polyether diol (PCMMO for short); wherein 3-chloromethyl-3-methyloxetane and 1 , The molar ratio of 4-butanediol is 8-60:1, and the molar ratio of boron trifluoride·tetrahydrofuran complex to 1,4-butanediol is 0.5-2:1.

Advantages of the present invention:

The PCMMO synthesis method of the invention is simple, the end group is a primary hydroxyl group with high reactivity, the molecular chain structure has certain symmetry, and can endow the polyurethane elastomer with higher mechanical properties. The tensile strength of the polyurethane elastomer prepared from the PCMMO of the present invention is 5.65 MPa, and the elongation is 486%, while the tensile strength of the PECH polyurethane elastomer in the comparative literature is 3.43 MPa, and the elongation is 375%.

Detailed ways

Below in conjunction with embodiment the invention will be further described.

test instrument:

(1) Infrared spectrum is tested by Nexus 870 Fourier Transform Infrared Spectrometer of American Nicolet Company;

(2) The nuclear magnetic resonance is tested by the AVANCE AV500 nuclear magnetic resonance instrument of the German Bruker company;

(3) The number average molecular weight is tested by GPC-50 gel permeation chromatograph of British PL company;

(4) The mechanical properties of the elastomer are tested by the Instron 4505 universal material testing machine of the American Instron Company;

(5) The hydroxyl value is tested by the phthalic anhydride-pyridine acylation method.

Example 1

Add 30ml of 1,2-dichloroethane, 1.8g (0.02mol) of 1,4-butanediol and 2.8 g (0.02mol) boron trifluoride tetrahydrofuran complex, after stirring for 30min at a temperature of 20°C, start to drop 24.1g (0.20mol) of 3-chloromethyl-3-methyloxetane , the dropwise addition time was 4h. After the dropwise addition, the reaction was continued for 24h, and the reaction was terminated by neutralizing with Na ₂ CO ₃ aqueous solution. The organic phase was washed with water until neutral, and after concentration, 24.7 g of a light yellow viscous liquid was obtained, with a yield of 95.4%.

Characterization data:

IR, ν _max (cm ^-1 ): 3387 (OH), 2967, 2934, 2879 (CH), 1109 (COC), 724 (C-Cl).

¹ H NMR (CD ₃ COCD ₃ , 500 MHz): 1.05, 3.37, 3.63.

¹³ C NMR (CD ₃ COCD ₃ , 500 MHz): 17.52, 41.42, 49.04, 73.56.

The number average molecular weight is 1210, and the hydroxyl value is 88.1mgKOH/g.

The above data indicate that the synthesized compound is a chlorinated polyether diol.

Example 2

Add 60ml of 1,2-dichloroethane, 1.8g (0.02mol) of 1,4-butanediol and 2.8 g (0.02mol) boron trifluoride tetrahydrofuran complex, after stirring for 30min at a temperature of 25°C, start to drop 38.6g (0.32mol) of 3-chloromethyl-3-methyloxetane , the dropwise addition time was 6h. After the dropwise addition, the reaction was continued for 30h, and the reaction was terminated by neutralizing with Na ₂ CO ₃ aqueous solution. The organic phase was washed with water until neutral, and after concentration, 39.1 g of a light yellow viscous liquid was obtained, with a yield of 96.8%.

The number average molecular weight is 2020, and the hydroxyl value is 52.2mgKOH/g.

Example 3

Add 90ml of 1,2-dichloroethane, 1.8g (0.02mol) of 1,4-butanediol and 4.2 g (0.03mol) boron trifluoride tetrahydrofuran complex, after stirring for 30min at a temperature of 25°C, start to drop 60.3g (0.50mol) of 3-chloromethyl-3-methyloxetane , the dropwise addition time was 6h. After the dropwise addition, the reaction was continued for 40h, and the reaction was terminated by neutralizing with Na ₂ CO ₃ aqueous solution. The organic phase was washed with water until neutral, and concentrated to obtain 60.4 g of light yellow viscous liquid with a yield of 97.3%.

The number average molecular weight is 3050, and the hydroxyl value is 34.5mgKOH/g.

Chlorinated polyether glycol application performance of the present invention

(1) Compatibility evaluation with isocyanate curing agent

The HDI trimer was selected as the curing agent, and the miscibility and reactivity between PCMMO and the curing agent were investigated.

The PCMMO and the HDI trimer of the present invention have good miscibility, the mixed solution is clear and transparent, and the formed mixed solution can stably undergo curing reaction at 60-80°C.

(2) Mechanical properties of elastomers

Using the PCMMO with the number average molecular weight of the present invention as 1210 as a raw material, mixing with curing agent HDI trimer and heating and curing, when the r value is 1.2, the mechanical properties of the prepared polyurethane elastomer: tensile strength is 5.65MPa, elongation was 486%.

Claims (2)

1. a kind of chlorinated polyether glycol, its structural formula is as shown in formula (I): Wherein, x+y=8-60, which is an integer. 2. a synthetic method of chlorinated polyether diol as claimed in claim 1, is characterized in that comprising the following steps: Add 1,2-dichloroethane, 1,4-butanediol and boron trifluoride tetrahydrofuran complex in sequence in a four-neck round bottom flask equipped with mechanical stirring, reflux condenser, thermometer and dropping funnel , after stirring at a temperature of 20°C to 30°C for 30 minutes, start to add 3-chloromethyl-3-methyloxetane dropwise, the dropwise addition time is 1h~8h, and continue to react for 24h~48h after the dropwise addition is completed , neutralized with Na ₂ CO ₃ aqueous solution, washed the organic phase with water until neutral, and concentrated to obtain chlorinated polyether diol; wherein 3-chloromethyl-3-methyloxetane and 1,4-butane The molar ratio of diol is 8-60:1, and the molar ratio of boron trifluoride·tetrahydrofuran complex to 1,4-butanediol is 0.5-2:1.