KR100540818B1 - Photodegradable compounds as a plasticizer of polyvinylchloride and polyvinylchloride blend containing the same - Google Patents

Abstract

In the present invention, TiO ₂ nanoparticles are bonded to a PVC plastic compound containing at least one selected from the group consisting of ester group (-COO-), hydroxyl group (-OH) and carboxyl group (-COOH) in the main chain or terminal. Disclosed is a compound for a photodegradable PVC plasticizer, characterized in that consisting of a composite. In the compound for photodegradable PVC plasticizer according to the present invention, since TiO ₂ nanoparticles, which are photocatalysts, are bonded to the PVC plastic compound and can be evenly dispersed in the PVC, it is possible to simply prevent the aggregation of photocatalytic particles generated when blending the photocatalyst particles. This can further promote photolysis of polyvinyl chloride (PVC) waste products.

Description

Photodegradable compounds as a plasticizer of polyvinylchloride and polyvinylchloride blend containing the same}

1 is a graph measured by light scattering spectroscopy of the particle diameter of the TiO ₂ nanoparticles before introduction into the photodegradable PVC according to the present invention,

2 is a graph showing characteristic peaks of Ti measured using X-ray photoelectron spectroscopy (XPS) for the compound for a photodegradable PVC plasticizer of the present invention to which TiO ₂ nanoparticles are bound;

Figure 3 is a graph showing the mass loss over time of PVC containing a photodegradable plasticizer according to the present invention under ultraviolet light conditions.

The present invention relates to a compound for a photodegradable PVC plasticizer, and in particular, since the TiO ₂ nanoparticles, which are photocatalysts, are bonded to the PVC plastic compound and can be dispersed evenly in the PVC, aggregation of the photocatalyst particles generated when blending the photocatalyst particles is simply performed. The present invention relates to a compound for photodegradable PVC plasticizer and a polyvinyl chloride blend containing the same, which can prevent the phenomenon and promote the photodegradation of polyvinyl chloride (PVC) waste products evenly.

Synthetic polymers represented by plastics, together with metals and ceramics, are one of the materials necessary for a convenient and comfortable modern life. Such synthetic polymer products are used in various industries, such as household goods, construction, medical, agriculture, the amount of use is increasing significantly. However, unlike natural polymers, most synthetic polymers are not easily decomposed, so the disposal and management of waste products made of these synthetic polymers has become a major social problem around the world.

In particular, PVC is a typical general-purpose resin, and can be easily designed from hard to soft by using properties such as excellent weather resistance, water resistance, chemical resistance, flame retardancy, and electrical insulation, and plasticizers and fillers, and thus, food packaging materials, storage containers, and toys for children. It is close to real life and widely used in various applications such as blood bag, sealant to prevent the opening of medicines.

However, PVC generates dioxin compounds, which are highly toxic environmental hormones, upon incineration for disposal after use. Dioxins are produced when incineration of organochlorine compounds and incomplete combustion of organic materials in the presence of chlorine and chlorine compounds. In particular, municipal waste incinerators contain a variety of dioxin-derived materials along with paper and garbage, and in particular, incinerators that burn wastes with high water content, dioxin is released without decomposition. According to international studies on the waste content on the production of dioxin, dioxin is the most produced from the soot gas from urban waste incinerators, and one of the main substances that dioxin generates is plastic such as PVC. It is becoming. Dioxins generated in this way pollute the air, agricultural products, rivers, soils, etc., and eventually, through the accumulation of food chains, are toxic to end-users, threatening not only ecosystem destruction but also human persistence.

There are two main ways to reduce the release of hazardous environmental hormone substances such as dioxins produced by incineration of PVC waste. The first method is to improve the combustion conditions and to completely treat the exhaust gas, thereby improving the problems caused by the conventional incineration treatment. However, most of them are small incinerators, and there are many difficulties in applying this method because the waste contains a lot of components including water. The second method is to fundamentally block dioxin generation by incineration process by developing waste treatment method by oxidation process such as ozone or UV irradiation or by developing photodegradable PVC material incorporating photocatalyst with catalytic decomposition activity. to be.

Since ozone oxidation requires a process of neutralizing ozone, which is harmful to the human body, the process is complicated. Therefore, research on a method of manufacturing a photodegradable PVC material using a photocatalyst has been actively conducted.

TiO ₂ nanoparticles are attracting attention as photocatalysts for the development of photodegradable PVC materials. TiO ₂ nanoparticles of several nanometers or tens of nanometers generate active oxygen compounds having decomposition properties for organic compounds by oxidation-reduction reactions under ultraviolet light or sunlight. Many studies have been made because of the property of complete or efficient decomposition. Patents and papers have published examples of the organic decomposition and antimicrobial properties that can be applied to architecture, wallpaper, sheets, automotive interiors, lamps, safety glasses, air conditioners, microwave ovens, flooring materials, refrigerators, and the like.

However, the method for producing a photodegradable PVC using a conventional TiO ₂ nanoparticles are makin made up because directly mixed with PVC and the physical to TiO ₂ nanoparticles in powder form, the nanoparticles because it is easy to size the less cohesive the PVC There are many difficulties to distribute evenly. Therefore, not only the part of the PVC waste in which TiO ₂ nanoparticles are not dispersed is not decomposed, and in order to solve this problem, an excessive amount of TiO ₂ nanoparticles are mixed to increase manufacturing cost and There is a problem that the physical properties are lowered.

Accordingly, the present invention solves the above problems, since the TiO ₂ nanoparticles, which are photocatalysts, are bonded to the PVC plastic compound and thus can be uniformly dispersed in the PVC, thereby preventing the aggregation of the photocatalytic particles generated when the photocatalyst particles are blended. The present invention provides a compound for a photodegradable PVC plasticizer and a polyvinyl chloride blend containing the same, which can promote photodegradation of polyvinyl chloride (PVC) waste products evenly.

In order to achieve the above technical problem, the present invention is a PVC plastic compound containing at least one selected from the group consisting of ester group (-COO-), hydroxyl group (-OH) and carboxyl group (-COOH) in the main chain or terminal It provides a compound for a photodegradable PVC plasticizer, characterized in that consisting of a composite bonded to TiO ₂ nanoparticles.

In the compound for a photodegradable PVC plasticizer according to the present invention, the PVC plastic compound may be a phthalate liquid low molecular compound, and it is more preferable to use a polymer compound containing a lactone repeat unit to prevent the plasticizer from leaking out. Do.

In the compound for a photodegradable PVC plasticizer according to the present invention, as the polymer containing a lactone repeating unit, any polymer compound capable of bonding TiO ₂ nanoparticles and not leaking out of the PVC can be used, A higher branched aliphatic polyester formed by self-condensation of alpha-carboxy-omega-2,2- [bis (hydroxymethyl) propanoate] polyester represented by the following formula (1); Or a higher branched aliphatic polyester formed by the self-condensation reaction of 2,2-bis (omega-hydroxy polyestermethyl) propionic acid represented by the following formula (2);

로 표시되며 a, b, c, d 및 e는 각각 0 이상의 정수로서 a+b+c+d+e는 1 이상이다. In Formulas 1 and 2, m is an integer of 1 to 15, n is an integer of 1 to 100 as the number of repeating units of the lactone-based monomer, R is hydrogen bonded to a central carbon atom or as a substituent independent of each other

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more.

In addition, in the compound for a photodegradable PVC plasticizer according to the present invention, the polymer containing a lactone repeating unit, a linear aliphatic polyol represented by the following formula (3), a cyclic aliphatic polyol represented by the following formula (4), To a polyol central molecule containing a plurality of hydroxy reactors at the terminal, selected from the group consisting of a cyclic aromatic polyol represented by the above and a linear or cyclic aliphatic polyol containing a non-carbon atom represented by the following formula (6), It is preferable that it is a molded structure aliphatic polyester formed by ring-opening-polymerization of the lactone-type monomer shown.

로 표시되며 a, b, c, d 및 e는 각각 0 이상의 정수로서 a+b+c+d+e는 1 이상이고, R₁ ~ R_2n+2 중 2개 이상은

로서 m은 0 이상의 정수이다. In Formula 3, C _n is a linear aliphatic central carbon atom, n is an integer of 1 or more, R ₁ ~ R _{2n + 2} is an independent substituent to each other bonded to a central carbon atom

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more, and R ₁ to Two or more of R _{2n + 2}

M is an integer of 0 or more.

로 표시되며 a, b, c, d 및 e는 각각 0 이상의 정수로서 a+b+c+d+e는 1 이상이고, R₁ ~ R_2n 중 2개 이상은 로서 m은 0 이상의 정수이다.In Formula 4, C _n is a cyclic aliphatic central carbon atom, n is an integer of 3 or more, R ₁ ~ R _2n are mutually independent substituents bonded to the central carbon atom

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more, and R ₁ to At least two of R _2n are wherein m is an integer of 0 or more.

로 표시되며 a, b, c, d 및 e는 각각 0 이상의 정수로서 a+b+c+d+e는 1 이상이고, R₁ ~ R_4n+2 중 2개 이상은

로서 m은 0 이상의 정수이다. In Formula 5, C _{4n + 2} is a cyclic aromatic central carbon atom, n is an integer of 1 or more, R ₁ ~ R _{4n +2} is a mutually independent substituent bonded to a central carbon atom

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more, and R ₁ to Two or more of R _{4n + 2}

M is an integer of 0 or more.

로 표시되며 a, b, c, d 및 e는 각각 0 이상의 정수로서 a+b+c+d+e는 1 이상이고, R₁ ~ R_2n+2 중 2개 이상은

로서 m은 0 이상의 정수이다.In Formula 6, CONP is a linear or cyclic aromatic central carbon atom containing at least one non-carbon atom selected from the group consisting of oxygen, nitrogen and phosphorus, n is an integer of 1 or more, x, y and z are each 0 As an above-mentioned integer, x + y + z is 1 or more and R <_1> - R _{2n + 2} is an independent substituent to each other bonded to a central carbon atom

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more, and R ₁ to Two or more of R _{2n + 2}

M is an integer of 0 or more.

로 표시되며 a, b, c, d 및 e는 각각 0 이상의 정수로서 a+b+c+d+e는 1 이상이다.In Formula 7, n is an integer of 1 or more, and R is a substituent bonded to hydrogen or one or more carbon atoms constituting the ring

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more.

In addition, in the compound for photodegradable PVC plasticizer according to the present invention, the polymer containing a lactone repeating unit, a polyol core molecule formed by the reaction of the compound represented by the following formula (8) and the compound represented by the following formula (9) And it is preferable that it is a molded structure aliphatic polyester formed by ring-opening-polymerizing the C3-C15 lactone monomer.

The hydroxyl group contained in the aliphatic polyester can be used by modifying the carboxyl group through an oxidation reaction using chromium oxide, dimethyl sulfoxide, manganese compounds and the like.

Hereinafter, a compound for a photodegradable PVC plasticizer and a PVC blend including the same according to the present invention will be described in detail.

The present invention provides TiO ₂ nanoparticles bonded to a PVC plastic compound containing at least one selected from the group consisting of ester group (-COO-), hydroxyl group (-OH) and carboxyl group (-COOH) in the main chain or terminal. It is a compound consisting of complex. Since the TiO ₂ nanoparticles are uniformly dispersed in the PVC when blending the compound with PVC, it is possible to solve the aggregation problem of TiO ₂ nanoparticles according to the conventional physical mixing method.

Di [2-ethylhexyl] phthalate (hereinafter DOP), dibutyl phthalate, butylbenzyl phthalate, di [2-ethylhexyl] adipate, dihexyl phthalate, dipropyl phthalate, dicyclohexyl phthalate, dipentyl phthalate, di Phthalate liquid low-molecular plasticizers such as ethyl phthalate, and polymer plasticizers containing lactone repeating units have ester groups (-COO-) or hydroxyl groups (-OH) at their main chains or terminals, and TiO ₂ nanoparticles Coordination bond or hydrogen bond to a group or a hydroxyl group. In addition, the hydroxy group present at the end of the PVC plastic compound is oxidized using chromium oxide, modified chromium oxidant, dimethyl sulfoxide, manganese compound, and the like to be modified with a carboxyl group (-COOH) to bind TiO ₂ nanoparticles. It may be. In particular, in the compound for a photodegradable PVC plasticizer according to the present invention, when a polymer containing a lactone repeating unit is used as the PVC plastic compound, it is excellent in compatibility with PVC, but is a polymer unlike a conventional liquid low molecular plasticizer. There is no problem with the outflow of PVC. Polymers containing such lactone repeating units include both linear caprolactone copolymers disclosed in US Pat. No. 5,385,974, as well as higher branched aliphatic polyesters and molded aliphatic polyester compounds, which will be described later. In view of the above, it is preferable to use a compound having a branched structure such as a higher branched structure or a molded structured aliphatic polyester compound.

The TiO ₂ nanoparticles are bonded to the PVC plastic compound as follows. TiO ₂ dispersions and PVC plastic compounds of various structures are dissolved in a solvent. The solvent may be changed in various compositions such as water or a water / organic solvent mixed solution. The solution thus prepared is sufficiently stirred and dried to obtain a PVC plastic composite having TiO ₂ nanoparticles bound thereto. When the PVC plastic composite thus obtained is mixed with PVC at a constant ratio, the PVC plastic composite can be uniformly dispersed in the PVC to impart plasticity and photodegradability to the PVC.

Hereinafter, in the compound for photodegradable PVC plasticizer according to the present invention, a polymer compound having a branched structure that can be most preferably used as a PVC plastic compound will be described in detail.

Alpha-carboxy-omega-2,2- [bis (hydroxymethyl) propanoate] polyester represented by the formula (1) and 2,2-bis (omega-hydroxypolyestermethyl) propionic acid represented by the formula (2) Is a repeating unit obtained through the cationic ring-opening polymerization of the lactone monomer represented by the following formula (7).

<Formula 7>

로 표시되며 a, b, c, d 및 e는 각각 0 이상의 정수로서 a+b+c+d+e는 1 이상이다. 특히 바람직하게는 R은 알킬기, 알콕시기, 알킬에스테르기 및 이들의 주쇄 또는 측쇄에 질소와 인을 함유하는 치환기로 이루어진 군으로부터 선택된 어느 하나이다.In Formula 7, n is an integer of 1 or more, and R is a substituent bonded to hydrogen or one or more carbon atoms constituting the ring

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more. Especially preferably, R is any one selected from the group consisting of an alkyl group, an alkoxy group, an alkylester group and substituents containing nitrogen and phosphorus in their main or side chains.

Thus, alpha-carboxy-omega-2,2- [bis (hydroxymethyl) propanoate] polyester and 2,2-bis (omega-hydroxy polyestermethyl) propionic acid are ring-opened substituted lactone monomers It is a compound which introduce | transduced the compound into two hydroxy functional groups.

Therefore, the higher branched aliphatic polyester compound (hereinafter referred to as HBPE) is a polymer compound synthesized by self-condensing a monomer having one carboxyl functional group and two hydroxy functional groups. Referring to the method for producing HBPE according to an embodiment of the present invention, first, alpha-carboxy-omega-2,2- [bis (hydroxymethyl) propanoate] polyester represented by Chemical Formula 1 (hereinafter, Self-condensing SCAB2-1). Here, self-condensation means that the ester bond is generated by the condensation reaction between the carboxy group and the hydroxyl group, thereby growing into a polymer. At this time, condensation may occur at one or two of one SCAB2-1 unit. For example, if a condensation reaction occurs in one of the SCAB2-1 units at any stage in the reaction, the molecular structure represented by the following formula (10) is generated in the molecular structure of the resulting HBPE.

On the other hand, if a condensation reaction occurs in two of one SCAB2-1 unit at any stage in the reaction, the molecular structure represented by the following formula 11 is generated in the molecular structure of the resulting HBPE.

As the condensation reaction proceeds in two places in one SCAB2-1 unit, many branches are generated in the generated HBPE, thereby obtaining HBPE having a high density of branch structures.

In addition, a method of manufacturing HBPE according to another embodiment will be described.

The method of preparing HBPE according to another embodiment is also substantially the same as the method described above. First, 2,2-bis (omega-hydroxy polyestermethyl) propionic acid (hereinafter, referred to as SCAB2-2) represented by Chemical Formula 2 is self-condensed. Here, self-condensation means that the ester bond is formed by the condensation reaction between the carboxy group and the hydroxyl group, thereby growing into a polymer. At this time, condensation may occur at one or two of one SCAB2-2 unit. If a condensation reaction occurs in one of the SCAB2-2 units at any stage of the reaction, the molecular structure represented by the following formula (12) is generated in the molecular structure of the resulting HBPE.

On the other hand, if a condensation reaction occurs in two of one SCAB2-2 unit at any stage of the reaction, the molecular structure represented by the following formula (13) is generated in the molecular structure of the resulting HBPE.

As the condensation reaction proceeds in two places in one SCAB2-2 unit, many branches are generated in the generated HBPE, thereby obtaining HBPE having a high-density branch structure.

Meanwhile, in the linear aliphatic polyol central molecule represented by Chemical Formula 3, the linear aliphatic polyol central molecules where n is 1, 2, and 3 are represented by the following Chemical Formulas 3a, 3b, and 3c.

In addition, in the cyclic aliphatic polyol central molecule represented by Chemical Formula 4, the cyclic aliphatic polyol central molecules where n is 3 and 4 are represented by the following Chemical Formulas 4a and 4b.

In addition, in the cyclic aromatic polyol central molecule represented by Chemical Formula 5, the cyclic aromatic polyol central molecules where n is 1 and 2 are represented by the following Chemical Formulas 5a and 5b.

In addition, in the linear or cyclic aliphatic polyol central molecule containing a non-carbon atom represented by Chemical Formula 6, n, x, y and z each contain a non-carbon atom of 2, 1, 0, 0 and 0. Linear or cyclic aliphatic polyol central molecules are represented by the following formula (6a): linear or cyclic aliphatic polyol central molecules containing non-carbon atoms where n, x, y and z are 5, 1, 0, 0 and 0, respectively Is represented by the following formula (6b).

As such, since the polyol central molecule of Chemical Formulas 3 to 6 may have several to several tens or more substituents, a large number of terminal units are formed in the molded aliphatic polyester compound of the present invention having the central molecule, thereby further improving plasticization performance. .

On the other hand, the lactone-based monomer of the formula (7) which is ring-opened and bonded to the substituent of the polyol core molecule forms a main chain represented by the following formula (14), such lactone monomers β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone, tridecanolactone, pentadecanolactone, γ-pentadecanolactone and γ-valerolactone, and derivatives in which hydrogen in these monomers is substituted with R in formula (5) Etc. can be mentioned. In the molded structure aliphatic polyester compound, R ₁ ~ Substituents represented by R _{2n + 4} and R include an alkyl group, an alkoxy group, an alkylester group or those in which nitrogen, oxygen or phosphorus is contained in the main chain or side chain of these substituents.

In Formula 14, n is preferably 1 to 15 as an integer of 1 or more, m is preferably an integer of 1 to 100.

Looking at the manufacturing method of the molded aliphatic polyester compound is as follows.

For example, as the linear aliphatic polyol central molecule represented by Chemical Formula 3-1, n is 1, R ₁ , R ₂ , R ₃ are CH ₂ OH, and R ₄ is C ₂ H ₅ , which is trimethylolpropane. When using as a central molecule, and ring-opening polymerization using a lactone monomer represented by the formula (7), a globular shaped aliphatic polyester as shown in the following formula (15) is produced.

In addition, in the compound for photodegradable PVC plasticizer according to the present invention, a polyol central molecule formed by the reaction of the compound represented by the formula (8) and the compound represented by the formula (9) as the PVC plastic compound, having 3 to 15 carbon atoms The method for producing a molded structured aliphatic polyester formed by ring-opening polymerization of a lactone monomer is as described in Korean Patent Laid-Open Publication No. 2002-0045065.

Since the aliphatic polyester compounds having the branched structure described above have many branching units, there are few chain entanglements compared to linear polymers of the same molecular weight size, and therefore, there are few restrictions on molecular mobility. In addition, since it has a large number of terminal units, it shows excellent molecular mobility due to faster chain terminal motion. In addition, since the aliphatic polyester compound having a branched structure has a three-dimensional hemispherical three-dimensional molecular structure through the control of the higher order structure, when mixed with PVC can eliminate the chain entanglement of the PVC main chain to improve the molecular mobility of the PVC. Therefore, when used as a PVC plastic compound, aliphatic polyester compounds having a branched structure can impart excellent ductility to PVC unlike plasticizers composed of linear polymers.

As such, a photodegradable PVC plasticizer composed of a composite in which TiO ₂ nanoparticles are bonded to a PVC plastic compound containing an ester group (-COO-), a hydroxyl group (-OH), or a carboxyl group (-COOH) at its main chain or terminal; The blend ratio with PVC is preferably 5 to 80% by weight and 95 to 20% by weight of PVC, respectively.

Hereinafter, the present invention will be described in more detail with reference to Examples, and the scope of the present invention is not limited to the following Examples.

Preparation Example 1

This production example is alpha-carboxy-omega-2,2- [bis (hydroxymethyl) propanoate] poly (methyl-epsilon-) obtained through ring-opening polymerization of a 4-methyl-epsilon-caprolactone monomer as a PVC plastic compound. It is intended to illustrate a method for producing a composite in which TiO ₂ nanoparticles are bonded using a higher branched aliphatic polyester formed by a self-condensation polymerization reaction of caprolactone) (hereinafter M-SCAB2-1).

1) Synthesis step of 2,2-bis (phenyldioxymethyl) propionic acid

First, 25.0 g (187 mmol) of bismethylolpropionic acid, 42.6 g (280 mmol) of benzyl dimethyl acetal, 0.69 g (4 mmol) of para-toluenesulfonic acid and 100 ml of acetone solvent were added and stirred at room temperature to completely dissolve. I was. Then a few drops of 30% ammonium hydroxide and ethanol one-to-one mixed solution were added and the reaction was diluted by adding 400 ml of methylene chloride. The reaction was extracted with 25 ml of distilled water, the organic layer was separated, distilled, concentrated and recrystallized from methylene chloride. The precipitate was filtered and dried to synthesize 2,2-bis (phenyldioxymethyl) propionic acid with a yield of 90%.

2) introducing linear poly (methyl-epsilon-caprolactone) by cationic ring-opening polymerization of 4-methyl-epsilon-caprolactone monomer

Into a three-necked flask equipped with a Dean-Stark trap, 21.6 g (0.2 mol) of benzyl alcohol and 0.43 g (10 mmol) of Stanus octanoate (Sn (Oct) ₂ ), a cationic ring-opening polymerization catalyst, were placed. . 10 ml of toluene and 114 g (1 mol) of 4-methyl-epsilon-caprolactone were added to the reactor and stirred to completely dissolve the reactants, followed by reaction at 110 ° C. for 24 hours while purging nitrogen. After the completion of the reaction, the product was precipitated in 800 ml of cold methanol, and the precipitate was filtered and dried to yield an alpha-benzoate-omega-hydroxy poly (4-methyl-epsilon-caprolactone) having a yield of 95%.

3) functionalizing alpha-benzoate-omega-hydroxy poly (methyl-epsilon-caprolactone) to AB2 type

First, 5 g (1.7 mmol) of alpha-benzoate-omega-hydroxy poly (methyl-epsilon-caprolactone) obtained in 2) and 5 ml of tetrahydrofuran solvent were added to a three neck flask and stirred. To this reaction was added a solution obtained by dissolving 0.45 g (2.17 mmol) of 2,2-bis (phenyldioxymethyl) propionic acid and 0.87 g (3.33 mmol) of triphenylphosphine in 1) in a tetrahydrofuran solvent. . To the reaction was added 0.67 g (3.3 mmol) of diisopropyl azodicarboxylate and reacted for 12 hours. The reaction was precipitated in cold methanol, filtered and dried to synthesize alpha-benzoate-omega- [2,2-bis (phenyldioxymethyl) propanoate] poly (methyl-epsilon-caprolactone) (yield 80 %).

4) Alpha-benzoate-omega- [2,2-bis (phenyldioxymethyl) propanoate] The benzoate group of poly (methyl-epsilon-caprolactone) is converted to a carboxyl group and a phenyldioxy group to a hydroxyl group Steps to Obtain M-SCAB2-1

In a 1-neck flask, 4 g of alpha-benzoate-omega- [2,2-bis (phenyldioxymethyl) propanoate] poly (methyl-epsilon-caprolactone), 10 ml of tetrahydrofuran solvent and ethyl acetate 40 ml was added and stirred to dissolve completely. 0.4 g of a 10 wt% palladium catalyst adsorbed on activated carbon was added to the mixture, and a flask containing hydrogen gas was connected to the flask on one side, and a three-way coke connected to a pump for applying a vacuum to the other. Vacuum was removed from the reactor and filled with hydrogen gas again three times to replace the inside of the reactor under a hydrogen stream, and reacted with vigorous stirring for 24 hours. The reaction thus obtained was filtered to remove the palladium catalyst and precipitated in cold methanol. The precipitate was filtered off, washed twice with methanol and dried to prepare the desired monomer M-SCAB2-1 (yield 88%).

5) Self-condensation reaction of M-SCAB2-1

First, M-SCAB2-1 was added to a three-necked flask equipped with an argon gas inlet tube, a dehydration drying tube, and a mechanical stirrer, and para-toluenesulfonic acid was added as much as 0.5% of the weight of M-SCAB2-1. The temperature of the reactor was maintained at 140 ° C. and the argon gas was continuously flowed to remove the reaction by-product and water. After 2 hours from the start of the reaction, the argon gas input tube was removed, and the reaction was performed in a vacuum state for 1 hour by connecting a vacuum tube. The product obtained after the reaction was dissolved in tetrahydrofuran and precipitated in cold methanol. The precipitate was filtered and dried to prepare a higher branched aliphatic polyester (M-SCHPE-1) having a yield of 98%.

6) M-SCHPE-1 and TiO ₂ Preparing a composite to which nanoparticles are bound

1 ml of Ti [OCH (CH ₃ ) ₂ ] ₄ was completely dissolved in 20 mL of ethanol, and then slowly added dropwise to 200 ml of an aqueous solution of pH 1.5 with stirring, followed by hydrolysis to obtain a transparent TiO ₂ aqueous solution. . The TiO ₂ aqueous solution thus obtained was evaporated at 35 ° C. using a rotavapor and dried for 4 hours at 60 ° C. in a vacuum oven to obtain TiO ₂ particles as white powder, which was then water at a constant ratio (0.5 g / L). It was dissolved in and the pH was 2.8 to obtain a stable TiO ₂ dispersion. Subsequently, M-SCHPE-1 synthesized with TiO ₂ particles was dissolved in a water / tetrahydrofuran (THF) (50/50) solution, and dried after 4 hours to prepare a composite having TiO ₂ introduced therein.

Preparation Example 2

This preparation example is a 2,2-bis [omega-hydroxy poly (methyl-epsilon-caprolactone) methyl] propionic acid (hereinafter M-SCAB2) obtained through ring-opening polymerization of a 4-methyl-epsilon-caprolactone monomer as a PVC plastic compound. It is to illustrate a method for producing a composite in which TiO ₂ nanoparticles are bound using a higher branched aliphatic polyester formed by the self-condensation polymerization reaction of -2).

1) Synthesis of 2,2-bis (hydroxymethyl) propyl benzoate

First, 9 g (67 mmol) of bis-MPA, 4.3 g (77 mmol) of sodium hydroxide and 50 ml of N, N-dimethylformamide solvent are added to a three neck flask. Subsequently, the mixture was warmed to 100 ° C., stirred for 1 hour, and completely dissolved therein. Then, 13.8 g (80 mmol) of benzyl bromide was slowly added dropwise and reacted for 20 hours. After completion of the reaction, the solvent in the reaction was evaporated and the remainder was dissolved in 200 ml of diethyl ether, and then extracted three times with 100 ml of distilled water to remove the unreacted substance and the solvent was evaporated again. The solid product thus obtained was recrystallized with toluene to prepare 2,2-bis (hydroxymethyl) propyl benzoate with a yield of 85%.

2) introducing linear poly (methyl-epsilon-caprolactone) by cationic ring-opening polymerization of 4-methyl-epsilon-caprolactone monomer into 2,2-bis (hydroxymethyl) propyl benzoate

44.8 g (0.2 mol) of 2,2-bis (hydroxymethyl) propyl benzoate obtained from 1) in a three-necked flask equipped with a Dean-Stark trap, Stanus Octanoate, a cationic ring-opening polymerization catalyst 0.43 g (10 mmol) of (Sn (Oct) ₂ ) was added thereto. 10 ml of toluene and 114 g (1 mol) of 4-methyl-epsilon-caprolactone were added to the reactor and stirred to completely dissolve the reactants, followed by reaction at 110 ° C. for 24 hours while purging nitrogen. After the completion of the reaction, the product was precipitated in 800 ml of cold methanol, and the precipitate was filtered and dried to yield a yield of 95% 2,2-bis [omega-hydroxy poly (methyl-epsilon-caprolactone) methyl] propyl benzoate.

3) reducing 2,2-bis [omega-hydroxy poly (methyl-epsilon-caprolactone) methyl] propyl benzoate to M-SCAB2-2

4 g of 2,2-bis [omega-hydroxy poly (methyl-epsilon-caprolactone) methyl] propyl benzoate, 10 ml of tetrahydrofuran solvent and 40 ml of ethyl acetate were added to a 1-neck flask and completely dissolved by stirring. . 0.4 g of a 10% palladium catalyst adsorbed on activated carbon was added to the mixture, and a flask connected to a balloon containing hydrogen gas on one side and a three-way coke connected to a pump for vacuuming on the other side. Vacuum was removed from the reactor and filled with hydrogen gas again three times to replace the inside of the reactor under a hydrogen stream, and reacted with vigorous stirring for 24 hours. The reaction thus obtained was filtered to remove the palladium catalyst and precipitated in cold methanol. The precipitate was filtered off, washed twice with methanol and dried to prepare the desired monomer M-SCAB2-2 (yield 92%).

Hereinafter, the self-condensation reaction of the monomer M-SCAB2-2, and then a method for producing a composite with TiO ₂ nanoparticles is the same as in Preparation Example 1.

Preparation Example 3

This preparation example uses trimethylolpropane (C (CH ₂ OH) ₃ C ₂ H ₅ ) having three hydroxy functional groups as a PVC plastic compound as a central molecule and an epsilon-caprolactone monomer having 6 carbon atoms as a lactone monomer. It is to illustrate a method for producing a composite in which TiO ₂ nanoparticles are bonded using a molded structure aliphatic polyester synthesized by cationic ring-opening polymerization.

13.4 g (0.1 mol) of trimethylolpropane and 0.13 g (3 mmol) of Stanus octanoate (Sn (Oct) ₂ ), a cationic ring-opening polymerization catalyst, were placed in a two-necked flask installed in a thermostat connected to a temperature controller capable of controlling temperature. Put in. 50 ml of toluene and epsilon-caprolactone were added to the reactor in the amounts shown in Table 1 and stirred to completely dissolve the reactants, and then reacted at 110 ° C. for 24 hours while purging nitrogen. After the reaction was completed, the product was precipitated in 800 ml of cold methanol, and the precipitate was filtered and dried to obtain a polymorphic poly (epsilon-caprolactone) having a branched number 3 (3-arm). Hereinafter, the method for producing a composite in which the obtained molded structure poly (epsilon-caprolactone) and TiO ₂ nanoparticles are bonded is the same as in Preparation Example 1.

Preparation Example 4

This production example is made of hexahydroxycyclohexane (C ₆ H ₆ (OH) ₆ ) having six hydroxy functional groups as one of the cyclic aliphatic polyol central molecules as a PVC plastic compound, and a carbon number as a lactone monomer. Cation ring-opening polymerization of the epsilon-caprolactone monomer of 6 is used to exemplify a method for preparing a composite in which TiO ₂ nanoparticles are bonded by using a molded aliphatic polyester.

18 g (0.1 mol) of hexahydroxycyclohexane, 0.18 g (4 mmol) of hexahydroxycyclohexane (Sn (Oct) ₂ ), a cationic ring-opening polymerization catalyst, in a two-necked flask installed in a thermostat connected to a temperature controller to control the temperature Put it. 50 ml of toluene and epsilon-caprolactone were added to the reactor in the amounts shown in Table 3 and stirred to completely dissolve the reactants, followed by reaction at 110 ° C. for 24 hours while purging nitrogen. After the reaction was completed, the product was precipitated in 1500 ml of cold methanol, and the precipitate was filtered and dried to obtain a polymorphic poly (epsilon-caprolactone) having a branched number 6 (6-arm). Hereinafter, the method for producing a composite in which the obtained molded structure poly (epsilon-caprolactone) and TiO ₂ nanoparticles are bonded is the same as in Preparation Example 1.

Preparation Example 5

This production example is a PVC plastic compound, one of the cyclic aromatic polyol core molecule, trihydroxy benzene (C ₆ H ₃ (OH) ₃ ) having three hydroxy functional groups as a central molecule, and a lactone-based monomer having 6 carbon atoms Cation ring-opening polymerization of the phosphoryl epsilon-caprolactone monomer is used to illustrate a method for producing a composite in which TiO ₂ nanoparticles are bonded using a molded aliphatic polyester.

12.6 g (0.1 mol) of trihydroxybenzene, 0.13 g (3 mmol) of Stanus octanoate (Sn (Oct) ₂ ), a cationic ring-opening polymerization catalyst, in a two-necked flask installed on a thermostat connected to a temperature controller to control the temperature Put it. 50 ml of toluene and epsilon-caprolactone were added to the reactor in the amounts shown in Table 4 and stirred to completely dissolve the reactants, and then reacted at 110 ° C. for 24 hours while purging nitrogen. After the reaction was completed, the product was precipitated in 800 ml of cold methanol, and the precipitate was filtered and dried to obtain a polymorphic poly (epsilon-caprolactone) having a branched number 3 (3-arm). Hereinafter, the method for producing a composite in which the obtained molded structure poly (epsilon-caprolactone) and TiO ₂ nanoparticles are bonded is the same as in Preparation Example 1.

Preparation Example 6

This preparation example is one of the linear aliphatic polyol central molecules containing a non-carbon atom as a PVC plastic compound, which has six hydroxy functional groups ((CH ₂ OH) ₃ CCH ₂ OCH ₂ C (CH ₂ OH) ₃ C) ring-opening polymerization of an epsilon-caprolactone monomer having 6 carbon atoms as a lactone-based monomer, to illustrate a method for preparing a composite having TiO ₂ nanoparticles bonded using a molded aliphatic polyester.

Dipentaerythritol 25.4g (0.1 mol) in a two-necked flask installed in a thermostat connected to a temperature controller capable of controlling temperature, and Sterner's Octanoate (Sn (Oct) ₂ ) 0.25g (6 mmol) cationic ring-opening polymerization catalyst Put it. 50 ml of toluene and epsilon-caprolactone were added to the reactor in the amounts shown in Table 5 and stirred to completely dissolve the reactants, and then reacted at 110 ° C. for 24 hours while purging nitrogen. After the reaction was completed, the product was precipitated in 1500 ml of cold methanol, and the precipitate was filtered and dried to obtain a polymorphic poly (epsilon-caprolactone) having a branched number 6 (6-arm). Hereinafter, the method for producing a composite in which the obtained molded structure poly (epsilon-caprolactone) and TiO ₂ nanoparticles are bonded is the same as in Preparation Example 1.

Example 1

TiO ₂ -incorporated composite prepared in Preparation Example 1 and PVC were mixed with 4: 6 in 200 mL of tetrahydrofuran, followed by solution blending to prepare a photodegradable PVC incorporating TiO ₂ .

Example 2

A and is the TiO ₂ introduced by the same method as in Example 1 except that the composite incorporating the TiO ₂ in the above-described way to the linear poly epsilon caprolactone purchased from Aldrich Co., in place of the composite TiO ₂ is introduced in the Production Example 1 Photodegradable PVC was prepared.

Example 3

A photodegradable PVC having TiO ₂ introduced therein was prepared in the same manner as in Example 1 except that the hydroxy end group present in the TiO ₂ introduced composite of Preparation Example 1 was modified by a carboxyl group using a cron ion catalyst. Prepared.

Example 4

A and is the TiO ₂ introduced by the same method as in Example 1 except that the composite incorporating the TiO ₂ in the above-described way in Preparation Example 1 of dioctyl phthalate (DOP) TiO ₂ is introduced into the composite material instead of commercial liquid plasticizer Photodegradable PVC was prepared.

Comparative Example 1

1 ml of Ti [OCH (CH ₃ ) ₂ ] ₄ was completely dissolved in 20 mL of ethanol, and then slowly added dropwise to 200 ml of an aqueous solution of pH 1.5 with stirring, followed by hydrolysis to obtain a transparent TiO ₂ aqueous solution. The TiO ₂ aqueous solution thus obtained was evaporated at 35 ° C. using a rotavapor, and dried at 60 ° C. in a vacuum oven for 1 hour to obtain white powder TiO ₂ particles. Subsequently, after adding 1 g of TiO ₂ particles to 200 mL of tetrahydrofuran, the mixture was stirred well, 5 g of PVC was dissolved therein, and the solution was slowly dried at room temperature to prepare a photodegradable PVC.

Comparative Example 2

To 60 g of dioctylphthalate (DOP), a commercial liquid plasticizer, 0.5-2 g of TiO ₂ particles were added, followed by stirring well to disperse the particles evenly, to which 100 g of PVC was added, and gelation and fusion reaction at 160-190 ° C. The softened photodegradable PVC was prepared through.

In the above Examples and Comparative Examples, the TiO ₂ particles before introduction into the photodegradable PVC were measured by light scattering spectroscopy and ultraviolet-visible spectroscopy, and it was confirmed that nanoparticles of 10 nm or less were synthesized, respectively (see FIG. 1). ). In addition, the formation of the composite of the PVC plastic compound of the present invention and TiO ₂ nanoparticles was confirmed through the characteristic peak of Ti measured using X-ray photoelectron spectroscopy (XPS) (Fig. 2).

Table 1 below shows the domain sizes of TiO ₂ particles introduced into the photodegradable PVC according to Examples and Comparative Examples.

sample Comparative Example 1 Comparative Example 2 Example 1 Example 2 Example 3 Example 4 Dispersed TiO ₂ Size (nm) 100-300 100-200 10-50 30-150 10-50 30-150

Referring to Table 1, TiO ₂ particles of Examples 1 to 4 in which TiO ₂ particles were bonded to a plasticizer and then mixed with a PVC according to the present invention, were physically mixed with TiO ₂ particles directly to a conventional PVC, or It can be seen that the dispersibility is superior to Comparative Examples 1 and 2 physically mixed together. In particular, it can be seen that the photodegradable PVC of Examples 1 and 3, in which the composite of the polymer compound having the branched structure and the TiO ₂ particles are introduced, has more excellent dispersibility of the TiO ₂ particles. As such, when the TiO ₂ nanoparticle dispersibility is improved, the transparency, processability, and photocatalytic decomposition of the PVC product may be excellent.

In addition, in order to evaluate the photodegradation characteristics of the PVC with the photodegradable plasticizer according to the present invention, the molecular weight change for the PVC of Example 3 was measured under ultraviolet conditions. Molecular weight was measured using a gel permeation chromatography (GPC) (Gel Permeation Chromatography, GPC), the sample was not irradiated with UV as 100% shown in Table 2 the molecular weight change of PVC over time.

UV irradiation time Pre-decomposition chain (Mw = 80,000) (%) Decomposition chain (Mw≤40,000) (%) 0 100 0 1 week 78 22 2 weeks 47 53 3 weeks 15 85 4 Weeks 0 100

Referring to Table 2, as the UV irradiation time elapsed, the content of the chain showing a molecular weight smaller than the original molecular weight increased, and after 4 weeks of UV irradiation, all of the polymer chains were broken, indicating that the photolysis proceeded extensively.

On the other hand, under the ultraviolet light conditions, the mass loss of the PVC according to Example 1 incorporating the photodegradable plasticizer according to the present invention was measured and shown in FIG. Referring to FIG. 3, it can be seen that as UV irradiation time elapses, a certain portion of PVC is decomposed and released to the atmosphere, thereby decreasing its mass continuously.

In the compound for photodegradable PVC plasticizer according to the present invention, since TiO ₂ nanoparticles, which are photocatalysts, are bonded to the PVC plastic compound and can be evenly dispersed in the PVC, it is possible to simply prevent the aggregation of photocatalytic particles generated when blending the photocatalyst particles. This can further promote photolysis of polyvinyl chloride (PVC) waste products. In particular, when using a polymer compound having a branched structure as a PVC plastic compound, unlike liquid low-molecular-weight plasticizers are not eluted to the outside at all, it is possible to solve the problems of endocrine disruption and destruction of ecosystems caused by the dissolution of plasticizers. In addition, the dispersibility of TiO ₂ nanoparticles with respect to PVC is also better, which is more suitable for the purpose of the present invention.

Claims (10)

It consists of a complex in which TiO ₂ nanoparticles are bonded to a PVC plastic compound containing at least one selected from the group consisting of ester group (-COO-), hydroxyl group (-OH) and carboxyl group (-COOH) Compound for photodegradable PVC plasticizer, characterized in that. The compound of claim 1, wherein the PVC plastic compound is a phthalate liquid low molecular compound. The compound for photodegradable PVC plasticizer according to claim 1, wherein the PVC plastic compound is a high molecular compound containing a lactone repeating unit. According to claim 3, wherein the polymer containing a lactone repeating unit, Higher branched aliphatic polyesters formed by self-condensation of alpha-carboxy-omega-2,2- [bis (hydroxymethyl) propanoate] polyesters represented by Formula 1; or A compound for photodegradable PVC plasticizer, characterized in that; a higher branched aliphatic polyester formed by the self-condensation reaction of 2,2-bis (omega-hydroxy polyestermethyl) propionic acid represented by the following formula (2). <Formula 1>

<Formula 2>

In Formulas 1 and 2, m is an integer of 1 to 15, n is an integer of 1 to 100 as the number of repeating units of the lactone-based monomer, R is hydrogen bonded to a central carbon atom or as a substituent independent of each other

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more. The compound for photodegradable PVC plasticizer according to claim 4, wherein the hydroxyl group of the higher branched aliphatic polyester is modified with a carboxyl group. According to claim 3, wherein the polymer containing a lactone repeating unit, A linear aliphatic polyol represented by Formula 3, a cyclic aliphatic polyol represented by Formula 4, a cyclic aromatic polyol represented by Formula 5, and a linear or cyclic aliphatic polyol containing a non-carbon atom represented by Formula 6 Compound for photodegradable PVC plasticizer, characterized in that the molded structure is an aliphatic polyester formed by ring-opening polymerization of the lactone-based monomer represented by the following formula (7) to a polyol central molecule containing a plurality of hydroxy reactors at the terminal, selected from the group consisting of . <Formula 3>

In Formula 3, C _n is a linear aliphatic central carbon atom, n is an integer of 1 or more, R ₁ ~ R _{2n + 2} is an independent substituent to each other bonded to a central carbon atom

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more, and R ₁ to Two or more of R _{2n + 2}

M is an integer of 0 or more. <Formula 4>

In Formula 4, C _n is a cyclic aliphatic central carbon atom, n is an integer of 3 or more, R ₁ ~ R _2n are mutually independent substituents bonded to the central carbon atom

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more, and R ₁ to Two or more of R _2n

M is an integer of 0 or more. <Formula 5>

In Formula 5, C _{4n + 2} is a cyclic aromatic central carbon atom, n is an integer of 1 or more, R ₁ ~ R _{4n +2} is a mutually independent substituent bonded to a central carbon atom

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more, and R ₁ to Two or more of R _{4n + 2}

M is an integer of 0 or more. <Formula 6>

In Formula 6, CONP is a linear or cyclic aromatic central carbon atom containing at least one non-carbon atom selected from the group consisting of oxygen, nitrogen and phosphorus, n is an integer of 1 or more, x, y and z are each 0 As an above-mentioned integer, x + y + z is 1 or more and R <_1> - R _{2n + 2} is an independent substituent to each other bonded to a central carbon atom

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more, and R ₁ to Two or more of R _{2n + 2}

M is an integer of 0 or more. <Formula 7>

In Formula 7, n is an integer of 1 or more, and R is a substituent bonded to hydrogen or one or more carbon atoms constituting the ring

A, b, c, d and e are each an integer of 0 or more, and a + b + c + d + e is 1 or more. The compound for photodegradable PVC plasticizer according to claim 6, wherein the hydroxyl group of the molded aliphatic polyester is modified with a carboxyl group. According to claim 3, wherein the polymer containing a lactone repeating unit, Photo-degradation, characterized in that the polyol formed by the reaction of the compound represented by the formula (8) and the compound represented by the formula (9) and the ring-structured aliphatic polyester formed by ring-opening polymerization of a C3-C15 lactone monomer Polymeric compound for the PVC plasticizer. <Formula 8>

<Formula 9>

In Formula 9, n is 3 to 189, and X is COOH, Br, or Cl. The compound for photodegradable PVC plasticizer according to claim 8, wherein the hydroxyl group of the molded aliphatic polyester is modified with a carboxyl group. A PVC blend comprising 5 to 80% by weight of the compound for photodegradable PVC plasticizer of claim 1 and 95 to 20% by weight of PVC.

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