KR102680393B1 - Polyoxyalkylene resin and method for producing the same - Google Patents

Abstract

The polyoxyalkylene resin of the present invention can have excellent thermal stability and mechanical properties such as impact strength, tensile strength, and flexural strength by using a catalyst that polymerizes by delaying the polymerization initiation rate. In addition, it has the advantage of having a low amount of formaldehyde generation and a high melting point.

Description

Polyoxyalkylene resin and method for producing the same {POLYOXYALKYLENE RESIN AND METHOD FOR PRODUCING THE SAME}

The present invention relates to polyoxyalkylene resin and its production method.

Polyoxymethylene (POM) resin has excellent mechanical properties, creep resistance, fatigue resistance, and friction and wear resistance, so it is widely used in places that meet complex requirements, such as various electrical and electronic components and mechanical mechanisms. .

In general, polyoxymethylene resin is prepared by bulk polymerization, solution polymerization, or suspension polymerization of trioxane or trioxane and cyclic ether and/or cyclic acetal to produce oxymethylene homopolymer or copolymer. However, these polyoxymethylene resins, especially polyoxymethylene homopolymers, lack thermal stability and have the disadvantage of being prone to decomposition during molding processing, thermally, mechanically, or due to additives. In particular, if unstable ends exist in the resin, it causes an increase in odor and poor processability during molding.

In order to overcome these disadvantages of polyoxymethylene homopolymer, a copolymer obtained by copolymerizing a specific comonomer, that is, a cyclic ether such as ethylene oxide or a cyclic formal such as dioxolane, with formaldehyde, trioxane, etc. in the presence of a catalyst. A method of randomly dispersing and introducing into the homopolymer is also proposed.

In addition, when the polymerization start time of the catalyst is too fast when polymerizing the polyoxymethylene resin, the molecular weight distribution of the polymer increases, thereby causing problems such as deterioration of thermal properties or mechanical properties. To solve this problem, there is a need to develop a catalyst that delays the polymerization initiation rate. In addition, when using a catalyst that delays the polymerization start time, problems with depolymerization due to polymerization delay may occur, so it is necessary to develop a catalyst that simultaneously solves this problem.

However, conventional polymerization catalysts could not sufficiently solve the above problems, and therefore, research and development on new polymerization catalysts for polyoxymethylene resin polymerization is urgently needed.

The purpose of the present invention to solve the above problems is to provide a method for producing a new polyoxyalkylene resin that has a longer polymerization start time than before, has a low amount of formaldehyde, and has excellent thermal stability and mechanical properties, and a polyoxy produced therefrom. To provide an alkylene resin.

As a result of continuous research by the present inventors to achieve the above-mentioned object, when polyoxyalkylene resin is manufactured using a specific amount of a new polymerization catalyst, polymerization occurs at a slower polymerization initiation rate than the conventional one, and the resulting resin also has excellent mechanical properties. The present invention was completed by discovering that it was possible to manufacture a resin with physical and thermal properties.

The present invention provides a polyoxyalkylene resin prepared from a polymer composition comprising a cyclic acetal monomer and a cyclic boron trifluoride compound.

According to one embodiment of the present invention, the cyclic boron trifluoride may have a carbon number of C3-30.

According to one embodiment of the present invention, the cyclic boron trifluoride compound may be represented by the following formula (1).

[Formula 1]

According to one embodiment of the present invention, the cyclic boron trifluoride may be included in an amount of 0.01 to 3 parts by weight based on 100 parts by weight of the cyclic acetal monomer.

According to one embodiment of the present invention, the cyclic acetal monomer may have C2-15 carbon atoms.

According to one embodiment of the present invention, the cyclic acetal monomer may further include dioxane, trioxane, and tetraoxane monomers, for example, 1,3-dioxolane and 1,3,5-trioxane. It may mainly include one or two or more selected from the group consisting of etc.

According to one embodiment of the present invention, the cyclic acetal monomer may be included in an amount of 90% by weight or more based on the total polymer composition.

According to one embodiment of the present invention, the polymer composition may further include a linear acetal monomer.

According to one embodiment of the present invention, the linear acetal monomer may be included in an amount of 0.01 to 5 parts by weight based on 100 parts by weight of the cyclic acetal monomer.

According to one embodiment of the present invention, the polymer composition may further include a comonomer such as a cyclic ether-based monomer or a cyclic formal-based monomer in addition to the monomers. Cyclic ethers include ethylene oxide, propylene oxide, butylene oxide, and phenylene oxide, and cyclic formals include 1,3-dioxolane, diethylene glycol formal, 1,3-propanediol formal, 1,4-butanediol formal, 1,4-butanediol formal, 1,3-dioxetane, 1,3,5-trioxetane, 1,3,6-trioxocane, etc.

According to one embodiment of the present invention, the polyoxyalkylene resin may include a repeating unit represented by the following formula (2).

[Formula 2]

In Formula 2,

R ₁ and R ₂ are independently hydrogen, methyl, or ethyl, and n is an integer of 1 or more.

According to one embodiment of the present invention, the polyoxyalkylene resin may have an initial propagation time of 4 seconds or more during polymerization.

According to one embodiment of the present invention, the polyoxyalkylene resin may have a melting point (Tm) of 170°C or higher.

The polyoxyalkylene resin of the present invention has a slower polymerization initiation rate than the conventional one, so polymerization begins after monomers and dispersion are well distributed, and the mechanical and thermal properties of the resulting resin are very excellent, that is, excellent thermal properties. It can have mechanical properties such as stability, impact strength, tensile strength, and flexural strength.

In addition, the amount of formaldehyde generated is low and it has a high melting point, so it also has excellent thermal properties.

Hereinafter, the present invention will be described in more detail through specific examples or examples including the attached drawings. However, the following specific examples or examples are only a reference for explaining the present invention in detail, and the present invention is not limited thereto, and may be implemented in various forms.

Additionally, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. The terminology used in the description herein is merely to effectively describe specific embodiments and is not intended to limit the invention.

Additionally, as used in the specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to also include the plural forms, unless the context clearly dictates otherwise.

In addition, units used in this specification without special mention are based on weight, and as an example, units of % or ratio mean weight % or weight ratio, and weight % refers to the composition of any one component of the entire composition unless otherwise defined. It refers to the weight percent occupied within.

Additionally, in this specification, when a part “includes” a certain element, this means that it may further include other elements rather than excluding other elements, unless specifically stated to the contrary.

In addition, the numerical range used in this specification includes the lower limit and upper limit and all values within the range, increments logically derived from the shape and width of the defined range, all double-defined values, and the upper limit of the numerical range defined in different forms. and all possible combinations of lower limits. Unless otherwise specified in the specification of the present invention, values outside the numerical range that may occur due to experimental error or rounding of values are also included in the defined numerical range.

As used herein, the term “resin” refers to a polymer and includes polymers and copolymers.

The term “alkyl” in this specification includes both straight chain and branched forms, and may have 1 to 30 carbon atoms, specifically 1 to 20 carbon atoms.

Hereinafter, the polyoxyalkylene resin and its manufacturing method according to an embodiment of the present invention will be described in more detail.

The present invention provides a polyoxyalkylene resin prepared from a polymer composition comprising a cyclic acetal monomer and a cyclic boron trifluoride compound.

According to one embodiment of the present invention, the cyclic boron trifluoride is a cyclic BF ₃ coordination compound polymerization catalyst, and the carbon number may be C3-30, C3-15, C3-10, C3-7, or C3-5. .

According to one embodiment of the present invention, the cyclic boron trifluoride compound may be represented by the following formula (1).

[Formula 1]

According to one embodiment of the present invention, the cyclic boron trifluoride compound may be included in an amount of 0.01 to 3 parts by weight, 0.01 to 1 part by weight, 0.05 to 0.5 parts by weight, or 0.1 to 0.3 parts by weight based on 100 parts by weight of the cyclic acetal monomer. You can.

When the above catalyst is used, the polymerization start time targeted in the present invention can be delayed, and the polymer produced therefrom has excellent thermal and mechanical properties, and the amount of formaldehyde generated can be dramatically reduced. .

According to one embodiment of the present invention, the cyclic acetal monomer may have carbon atoms of C1-30, C1-15, C2-15, C2-10, or C2-5.

According to one embodiment of the present invention, the cyclic acetal monomer may include any one or two or more selected from the group consisting of 1,3-dioxolane, 1,3,5-trioxane, etc. Preferably, it may be trioxane or a mixture of trioxane and dioxolane.

According to one embodiment of the present invention, the cyclic acetal monomer may include a type of cyclic acetal monomer different from trioxane. Examples of the cyclic monomer may further include comonomers such as cyclic ether monomers or cyclic formal monomers. Cyclic ethers include ethylene oxide, propylene oxide, butylene oxide, and phenylene oxide, and cyclic formals include 1,3-dioxolane, diethylene glycol formal, 1,3-propanediol formal, 1,4-butanediol formal, 1,4-butanediol formal, 1,3-dioxetane, 1,3,5-trioxetane, 1,3,6-trioxocane, etc.

At this time, other types of cyclic acetal monomers may be included in an amount of 0.1 to 100 parts by weight, 1 to 50 parts by weight, or 3 to 15 parts by weight based on 100 parts by weight of trioxane, but are not limited thereto.

According to one embodiment of the present invention, the cyclic acetal monomer may be included in an amount of 90% by weight or more, 90 to 99.9% by weight, or 95 to 99.5% by weight, based on the total polymer composition.

According to one embodiment of the present invention, the polymer composition may further include an alkyl-substituted phenol or acetal as a chain transferring agent, and may preferably include a linear acetal compound. The linear acetal compound may have a carbon number of C1-30, C1-15, C2-15, C2-10, or C2-7. Non-limiting examples of the linear acetal monomer include dimethoxymethane, dimethoxyethane, diethoxyethane, and diethoxymethane. The linear acetal monomer may be included in an amount of 0.01 to 50 parts by weight, 0.01 to 20 parts by weight, 0.01 to 5 parts by weight, or 0.1 to 3 parts by weight based on 100 parts by weight of the cyclic acetal monomer.

According to one embodiment of the present invention, the polymerization composition may further include a conventional or known polymerization inhibitor. When the molecular weight of polyoxyalkylene is obtained at 10,000 to 500,000 g/mol through the polymerization reaction of monomers, the polymerization reaction can be stopped by adding a polymerization terminator. The polymerization inhibitor can be used without limitation as long as it can effectively stop the polymerization reaction, for example, triphenyl phosphate, Bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, alkyl substituted form. Melamine-based polymerization inhibitors such as alkylated formamideacetal, hexamethoxymethylmelamine, hexaethoxymethylmelamine, hexapropoxymethylmelamine, and hexabutoxymethylmelamine can be used. The polymerization terminator can be added in an amount of 0.01 to 50 molar times, preferably 0.05 to 10 molar times, the amount of the polymerization catalyst.

Additionally, the polymerization terminator may be added as is or may be added dissolved in an organic solvent. At this time, organic solvents that can be used include aromatic hydrocarbons such as benzene, toluene, and xylene, aliphatic hydrocarbons such as n-hexane, n-heptane, and cyclohexane, alcohols such as methanol, chloroform, dichloromethane, 1,2 - Halogenated hydrocarbons such as dichloroethane, and ketones such as acetone and methyl ethyl ketone.

In one example of the present invention, additives commonly used in the relevant field may be further included, if necessary. Specifically, it may include, for example, antioxidants, formaldehyde or formic acid removers, end-group stabilizers, fillers, colorants, lubricants, mold release agents, antistatic agents, flame retardants, reinforcing agents, light stabilizers, pigments, etc. The content of the additive may be used within a range that does not substantially adversely affect the physical properties of the composition of the present invention. Specifically, examples of the antioxidant include sterically hindered bisphenol, for example, tetra-bis [methylene (3,5-dit-butyl-4-hydrocinnamate)] methane, Irganox 1010 from Ciba-Geigy. Products manufactured and sold under the brand name can be used.

According to one embodiment of the present invention, the polyoxyalkylene resin is manufactured by polymerizing the above-described cyclic acetal monomer under the above-described cyclic boron trifluoride compound polymerization catalyst, and is made of several types depending on the type of monomer additionally included. It can be manufactured as a copolymer (same as a copolymer) containing repeating units. Additionally, the polyoxyalkylene resin may be a random copolymer or a block copolymer.

The polymerization may be performed in the form of bulk polymerization, suspension polymerization, or solution polymerization, and the temperature during the polymerization reaction may be in the range of 0 to 100°C, preferably 20 to 80°C. Other conditions may be conventional or known conditions without limitation.

According to one embodiment of the present invention, the polyoxyalkylene resin may be a homopolymer containing only a single repeating unit, or a copolymer containing two or more types of repeating units. Specifically, the polyoxyalkylene resin may include a repeating unit represented by the following formula (2).

[Formula 2]

In Formula 2, R ₁ and R ₂ are independently hydrogen, methyl, or ethyl, and n is an integer of 1 or more.

According to one embodiment of the present invention, in Formula 2, R ₁ and R ₂ are independently hydrogen or methyl, and n may be 1 or 2.

According to another embodiment of the present invention, in Formula 2, R ₁ and R ₂ are independently hydrogen, methyl, or ethyl (not all hydrogen), and n may be 2 to 6.

According to one embodiment of the present invention, the polyoxyalkylene resin may have a weight average molecular weight of 10,000 to 500,000 g/mol, 20,000 to 200,000 g/mol, or 50,000 to 100,000 g/mol.

According to one embodiment of the present invention, the polyoxyalkylene resin may have a melting point (Tm) of 160°C or higher, 170°C or higher, 170 to 200°C, or 173 to 190°C.

According to one embodiment of the present invention, the polyoxyalkylene resin has a melt index (190°C 2.16 kg/10 min) of 10 g/10 min. or less, 9 g/10 min. or less, 0.01 to 8 g/10 min., 0.01 to 7.5. g/10 min. or 0.1 to 7.0 g/10 min.

According to one embodiment of the present invention, the polyoxyalkylene resin may have a tensile strength of 1 to 100 MPa, 10 to 90 MPa, 50 to 85 MPa, or 65 to 80 MPa.

According to one embodiment of the present invention, the polyoxyalkylene resin may have a yield elongation of 1 to 50%, 5 to 20%, or 7 to 15%.

According to one embodiment of the present invention, the polyoxyalkylene resin may have a flexural strength of 1 to 200 MPa, 10 to 150 MPa, 50 to 100 MPa, or 85 to 95 MPa.

According to one embodiment of the present invention, the polyoxyalkylene resin may have a flexural modulus of 1,000 to 10,000 MPa, 1,500 to 8,000 MPa, or 2,000 to 5,000 MPa.

According to one embodiment of the present invention, the polyoxyalkylene resin may have an impact strength of 1 to 50 kJ/m2, 5 to 20 kJ/m2, or 7 to 15 kJ/m2.

According to one embodiment of the present invention, the polyoxyalkylene resin may have a formaldehyde generation amount of 10 mg/kg or less, 9 mg/kg or less, 8 mg/kg or less, or 7 mg/kg or less, and more than 0 mg/kg.

According to one embodiment of the present invention, the polyoxyalkylene resin has a polymerization initiation speed (Initial Propagation Time, sec.) of 3 seconds or more, 4 seconds or more, 5 seconds or more, 6 seconds or more, or 6.5 seconds or more, It can be less than 20 seconds.

The present invention will be described in more detail below based on examples and comparative examples. However, the following Examples and Comparative Examples are only one example to explain the present invention in more detail, and the present invention is not limited by the following Examples and Comparative Examples.

[Physical property evaluation method]

1) Formaldehyde generation (E _CH2O )

According to the VDA275 standard, the obtained polyoxyalkylene resin composition is molded into sizes of 100 mm Х 40 mm Х 2 mm, then fixed in a 1 L bottle containing 50 ml of water without contacting the water, and then sealed. After the bottle equipped in this way was left at 60°C for 3 hours, the amount of formaldehyde generated in the molded product was measured by analyzing the color development of the formaldehyde content collected in water using a UV spectrophotometer. The smaller this value, the better the thermal stability.

2) Melt index (MI) [g/10min]

The weight of the resin sample extruded from an orifice of a constant inner diameter at a temperature of 190°C and a load of 2.16 kg for 10 minutes was measured. This value is a measure of evaluating the depolymerization rate of the resin. The larger the melt index value, the higher the depolymerization rate. It indicates high.

3) Weight average molecular weight (Mw) [g/mol]

The weight average molecular weight was measured using gel permeation chromatography (GPC) equipment manufactured by Futecs. The equipment consists of a mobile phase pump (Gradient Pump), a column heater (AT-4000), a detector (Shodex 201H R.I Detector), and an injector (NS-6000 automatic injector). The analysis column used was the HFIP 800 Series from Shodex and was used as a standard material. used 7 types of STDs of polymethyl methacrylic (PMMA). HPLC grade hexafluoroisopropanol (HFIP) is used as the mobile phase solvent, and the measurement is performed under the conditions of a column heater temperature of 40°C and a mobile phase solvent flow rate of 0.7 mL/min. Polyoxyalkylene prepared for sample analysis was dissolved in hexafluoroisopropanol (HFIP), a mobile phase solvent, and then injected into GPC equipment to measure the weight average molecular weight.

4) Tensile strength [MPa] and yield elongation [%]

Tensile strength was measured using a Universal Testing Machine (UTM) according to ISO 527-1 and ISO 527-2 standards, and the tensile specimens were evaluated five times for each sample at a crosshead speed of 50 mm/min and the average value was calculated.

5) Flexural strength and flexural modulus [MPa]

Flexural strength and elastic modulus were measured using UTM (Univesal Testing Machine) according to the ISO 178 standard, and each sample was evaluated five times and the average value was calculated.

6) Impact strength [kJ/㎡]

Charpy impact strength was measured using ISO 179-1 and ISO 179-2 standards, and notched specimens were used at room temperature (25°C) using Charpy impact tester No.258D manufactured by Yasuda Seiki. Impact strength was measured 5 times for each sample in a 25°C environment and the average value was calculated.

7) Melting point (Tm) [℃]

Measurements were made in an environment from 0°C to 230°C at a temperature increase rate of 10°C/min using a DSC (Differential Scanning Calorimetry) analysis device.

8) Initial Propagation Time (Tp) [s (seconds)]

The time for initial white turbidity to be generated was measured from the time the polymerization catalyst was added to the monomer. After a certain period of time after adding the polymerization catalyst to the monomer, white turbidity suddenly occurs. The point at which white turbidity suddenly occurs was observed using a high-speed camera capable of shooting over 50 frames per second, and the white turbidity occurs from the point of injection of the polymerization catalyst. The time until this point was recorded as the growth rate during polymerization.

[Example 1]

After maintaining the 1L capacity polymerization reactor at 50℃, inject 500g of Trioxane and 0.5g of Dimethoxymethane (Methylal) using a quantitative injection device, and then use Boron trifluoride Tetrahydrofuran as a polymerization catalyst. , 0.5 g of BF ₃ -THF) was added. 15 minutes after adding the polymerization catalyst, hexamethoxymethylmelamine (CYTEC, CYMEL303) was added as a polymerization terminator dissolved in benzene in an amount of 0.170 g, which is 1.0 molar times of the polymerization catalyst, and the reaction was completed after 10 minutes for 15 minutes. Afterwards, the reaction was completed to obtain polyoxymethylene resin.

The physical properties of the polyoxymethylene resin were evaluated using the measurement method described above, and the results are shown in Table 1 below.

[Example 2]

The same procedure as Example 1 was performed except that 1.0 g of BF ₃ -THF, a polymerization catalyst, was added.

[Example 3]

The same procedure as Example 1 was performed except that 1.5 g of BF ₃ -THF, a polymerization catalyst, was added.

[Example 4]

The same procedure as Example 1 was performed except that 1.0 g of dimethoxymethane was added.

[Example 5]

The same procedure as Example 4 was performed except that 1.0 g of BF ₃ -THF, a polymerization catalyst, was added.

[Example 6]

The same procedure as Example 4 was performed except that 1.5 g of BF ₃ -THF, a polymerization catalyst, was added.

[Example 7]

The same procedure as Example 1 was performed except that 1.5 g of dimethoxymethane was added.

[Example 8]

The same procedure as Example 7 was performed except that 1.0 g of BF ₃ -THF, a polymerization catalyst, was added.

[Example 9]

The same procedure as Example 7 was performed except that 1.5 g of BF ₃ -THF, a polymerization catalyst, was added.

[Example 10]

The same procedure as Example 6 was performed except that 10 g of dioxolane was added when trioxane was added.

[Example 11]

The same procedure as Example 6 was performed except that 20 g of dioxolane was added when trioxane was added.

[Example 12]

The same procedure as Example 6 was performed except that 30 g of dioxolane was added when trioxane was added.

[Comparative Example 1]

The same procedure as Example 4 was performed, except that the same amount of boron trifluoride diethyl etherate (BF ₃ OEt ₂ ) was added as the polymerization catalyst instead of BF ₃ -THF.

[Comparative Example 2]

The same procedure as in Example 5 was performed, except that the same amount of boron trifluoride diethyl etherate (BF ₃ OEt ₂ ) was added as a polymerization catalyst instead of BF ₃ -THF.

[Comparative Example 3]

The same procedure as Example 6 was performed, except that the same amount of boron trifluoride diethyl etherate (BF ₃ OEt ₂ ) was added as the polymerization catalyst instead of BF ₃ -THF.

[Comparative Example 4]

The same procedure as Example 11 was performed, except that the same amount of boron trifluoride diethyl etherate (BF ₃ OEt ₂ ) was added as the polymerization catalyst instead of BF ₃ -THF.

[Comparative Example 5]

The same procedure as Example 11 was performed, except that the same amount of boron trifluoride dimethyl etherate (BF ₃ OMe ₂ ) was added as the polymerization catalyst instead of BF3-THF.

MI Seal
robbery surrender
elongation curve
robbery curve
modulus of elasticity Shock
robbery Tm _ECH2O Tp unit g/10min MPa % MPa MPa kJ/㎡ ℃ mg/kg s Example 1 1.6 64 12 84 2,600 10 169 7.9 6.8 Example 2 3.2 66 11 88 2,650 8 170 8.2 6.9 Example 3 5.6 69 11 91 2,700 7 172 8.7 6.6 Example 4 2.2 69 12 90 2,700 13 170 7.8 6.1 Example 5 4.2 71 11 96 2,750 12 172 8.1 5.9 Example 6 6.8 74 11 97 2,850 11 175 8.8 6.2 Example 7 3.6 68 13 90 2,700 13 172 7.9 5.6 Example 8 6.0 71 12 92 2,750 12 174 8.2 5.3 Example 9 8.4 75 11 95 2,800 11 176 8.6 5.4 Example 10 6.6 69 10 91 2,700 12 171 6.0 6.4 Example 11 7.0 70 10 92 2,800 14 168 4.8 6.5 Example 12 6.9 64 9 87 2,650 13 166 4.2 6.8 Comparative Example 1 4.6 60 12 79 2,400 10 168 10.5 3.6 Comparative example 2 7.0 61 11 82 2,500 9 170 11.1 3.2 Comparative Example 3 9.2 63 10 84 2,600 8 172 11.8 2.8 Comparative example 4 8.8 60 10 83 2,550 9 168 6.8 2.9 Comparative Example 5 8.2 60 10 81 2500 9 165 9.9 2.2

As shown in Table 1, when a cyclic boron trifluoride compound was used as a polymerization catalyst, the polymerization initiation rate was significantly increased compared to the comparative examples. For example, when the catalyst of the present invention was used, the polymerization initiation rate was increased by more than two times in all examples, which means that polymerization could occur after the catalyst was sufficiently dispersed with the monomers, rather than immediately after being added. am. By extending this polymerization initiation rate, as seen in the present invention, when Example 4 and the same comparative example as Example 4 were used only as a catalyst that did not belong to the present invention, the tensile strength decreased from 69 to 60, and the flexural strength was It can be seen that the flexural modulus decreased from 90 to 79 and the flexural modulus decreased from 2700 to 2400, confirming that the mechanical properties were significantly increased by using the catalyst of the present invention.

In addition, the amount of formaldehyde generated in Example 4 increased from 7.8 mg/kg to 10.5 mg/kg compared to Comparative Example 1, showing that the catalyst of the present invention significantly reduces the amount of formaldehyde generated. In addition, it was confirmed from Table 1 above that an excellent synergistic effect was observed in thermal properties.

In addition, when comparing Example 5, Comparative Example 2, Example 6, Comparative Example 3, Example 11, and Comparative Example 4, which are the same embodiment, the polyoxymethylene resin according to one example has a remarkable It showed an increase in mechanical properties, an increase in thermal properties, and a low amount of formaldehyde generated.

Therefore, it was confirmed that a polyoxymethylene resin with a high melting point, excellent mechanical properties and thermal stability, and low formaldehyde generation can be produced by delaying the polymerization initiation rate according to the present invention.

As described above, the present invention has been described with specific details and limited embodiments, but these are provided only to facilitate a more general understanding of the present invention, and the present invention is not limited to the above embodiments, and the field to which the present invention pertains is not limited to the above embodiments. Those skilled in the art can make various modifications and variations from this description.

Accordingly, the spirit of the present invention should not be limited to the described embodiments, and the scope of the patent claims described later as well as all things that are equivalent or equivalent to the scope of this patent claim shall fall within the scope of the spirit of the present invention. .

Claims (13)

A polyoxyalkylene resin prepared from a polymer composition comprising a cyclic acetal monomer and a cyclic boron trifluoride compound,
The cyclic boron trifluoride compound is represented by the following formula 1,
The cyclic acetal monomer is 1,3,5-trioxane,
The polyoxyalkylene resin has a melt index (2.16 kg/10 min at 190°C) of 0.01 to 8.0 g/10 min.
[Formula 1]
delete delete According to paragraph 1,
A polyoxyalkylene resin wherein the cyclic boron trifluoride compound is contained in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the cyclic acetal monomer. delete delete According to paragraph 1,
A polyoxyalkylene resin containing 90% by weight or more of the cyclic acetal monomer based on the total polymer composition. According to paragraph 1,
The polymer composition is a polyoxyalkylene resin further comprising a linear acetal monomer. According to clause 8,
A polyoxyalkylene resin wherein the linear acetal monomer is contained in an amount of 0.01 to 5 parts by weight based on 100 parts by weight of the cyclic acetal monomer. delete According to paragraph 1,
A polyoxyalkylene resin containing a repeating unit represented by the following formula (2).
[Formula 2]

In Formula 2,
R ₁ and R ₂ are independently hydrogen,
n is 1. According to paragraph 1,
Polyoxyalkylene resin with a polymerization initiation speed (Initial Propagation Time, sec.) of 4 seconds or more. According to paragraph 1,
Polyoxyalkylene resin with a melting point (Tm) of 170°C or higher.