JPH0582419B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a soft plastic molded product of vinyl chloride resin used for covering agricultural greenhouses, greenhouses, heat insulation, etc. More specifically, the present invention relates to a soft plasticized vinyl chloride resin molded product that exhibits less volatilization of plasticizer, particularly excellent cold resistance, and no decrease in tear strength and impact strength. Prior Art Conventionally, soft plastic films or sheets made of vinyl chloride resin have been widely used as plasticized molding materials for covering agricultural greenhouses. As a plasticizer for these vinyl chloride resins, (1) di-2-ethylhexyl phthalate (hereinafter abbreviated as DOP) is mainly used, and (2) a volatile plasticizer manufactured from diol and adipic acid is used. Polyesters are used. However, the tear strength and impact resistance of DOP (1) become weak at low temperatures below 0° C., and it cannot be used in cold regions. The volatile plasticizers made of polyesters containing diol and adipic acid as main components mentioned in (2) above can be reacted with a diol component, a terminal monofunctional alcohol or a monobasic acid, and various types with different molecular weights can be used. There is something. Most of these polyesters have a molecular weight of 1,000 to 4,000, and the molecular weight distribution is not necessarily uniform, so the average value of the molecular weight is set to be higher than necessary in order to reduce volatility caused by low-molecular oligomers. There is. Dispersibility deteriorates as the molecular weight increases, and the plasticity is significantly inferior to DOP and DOA (di-2-ethylhexyl adipate).Therefore, this polyester is used in combination with DOP or DOA. This has traditionally been done. Purpose of the Invention The present invention was made in order to eliminate the drawbacks of conventional soft plastic molded vinyl chloride resin moldings.The purpose of the present invention is to create a molded product that does not lose its plasticity even after the summer, has excellent cold resistance, It is an object of the present invention to provide a soft plasticized vinyl chloride resin molded product that is suitable for use in cold regions without deterioration in tear strength and impact resistance. Composition of the Invention As a result of intensive research to achieve the above object, the present inventor has found that although conventional polyester plasticizers produced by the condensation reaction of adivic acid and diol have the drawbacks mentioned above, , the generated general formula RO―(CO(CH ₂ ) ₄ COOR′O)― _o CO
It has been found that a plasticized molded product of vinyl chloride resin using a complex ester represented by (CH ₂ ) ₄ COOR as a plasticizer can overcome the conventional drawbacks. The present invention was completed based on this knowledge. The gist of the invention is that the general formula RO—(CO(CH ₂ ) ₄ COOR′O)— _o CO produced by transesterification reaction
(CH ₂ ) ₄ COOR (where n = 1 to 5, R is an alkyl group with 2 to 9 carbon atoms, R' is 2 with a main chain of 2 to 9 carbon atoms)
The molecular weight (representing the diol of a functional alcohol or the alcohol residue of an ether alcohol) is 430 to 1000, and the viscosity is 20 to 1000.
This is a plasticizer for vinyl chloride resin that uses a composite ester with a temperature of 600 cps (21°C). The plasticizer for vinyl chloride resin of the present invention is used for molded products such as vinyl chloride resin films or sheets. The transesterification reaction in the present invention can be carried out by the following two methods. (1) Adipic acid and an excess amount of monofunctional alcohol are dehydrated and esterified in the presence of a dehydration esterification catalyst, such as butyl titanate, to produce dialkyl adipate. A method in which a 1/2 molar amount or less, preferably 1/3 to 1/5 molar amount of diol is added to this dialkyl adipate, and transesterification is carried out while performing a dealcoholization reaction. The theoretically necessary amount of adipic acid diester in this reaction is 2 mol per 1 mol of diol, but it is preferably in excess. If diol is used in excess, it is easy to produce a composite ester containing at least half of the bis compound represented by the above general formula where n=1 and has excellent plasticity while preventing the by-product of ester alcohol. It is. (2) During the usual production reaction of adipic acid diester, 2/3 molar amount or less, preferably 1/2 to 1/4 molar amount of diol is added to carry out the dehydration esterification reaction. A method of subsequently carrying out a dehydrated alcohol transesterification reaction. Also in this method, the reason why the amount of diol is preferably 1/2 to 1/4 mole is as described in the method (1) above. In any of the above methods, the product is produced through a dealcohol transesterification reaction. According to such a method, a complex ester containing a large amount of bis compounds with excellent plasticity can be easily produced, and the ester alcohol, which is a reaction intermediate that becomes a volatile factor of the complex ester, also reacts, and the reaction intermediate A complex ester containing no body is obtained. The molecular weight of the composite ester plasticizer used in the present invention is between 500 and 1000, which is between DOA and conventional polyesters, and its structure is diol bisalkyl adipate and composite ester oligomers similar to it, and its composition is as follows: It is indicated by. HOOC−A−COOH is adipic acid, HO−R′−
If OH is expressed as a difunctional diol and ROH is expressed as a monofunctional alcohol, and the acid and alcohol residues are respectively expressed as A, R and R', ROCOACOOR'-
OCOACOOR (diol bisalkyl adipate)
and RO―(COACOOR′O)― _o COACOOR(n is 2~
5). The reaction formula is as follows. HOCOACOOH+ROH→ROCOACOOR ROCOACOOR+HOR′OH→ RO(COACOOR′O) _o COACOOR HOCOACOOH+HOR′OH+ROH→ ROCOACOOR′OH+ROCOACOOR→ RO(COACOOR′O) _o COACOOR This diol bisalkyl adipate (hereinafter referred to as bis compound) is quantitatively produced. This is difficult, and oligomers with n=2 to 5 are produced as by-products. Even if this oligomer is not separated and purified, it is only necessary to remove volatile unreacted substances, and the inclusion of the oligomer will not significantly deteriorate the plasticity of the bis compound. However, as the amount of by-products and their molecular weight increase, the viscosity of the solution increases and the plasticity deteriorates. Adipic acid is used as the dibasic acid, but other dibasic acids may be used in combination. Diols of difunctional alcohols include diols having a main chain having 2 to 9 carbon atoms and diols having side chains, such as ethylene glycol, 1.2- or 1.3-propanediol, 1.3- or 1.4-butanediol. , 1.6-hexanediol, 2.2-dimethyl 1.3-propanediol, 2-
Examples include methyl 2-ethyl 1,3-propanediol, diethylene glycol, triethylene glycol, dipropylene glycol, and tribropylene glycol. The melting points of the bis compounds and oligomers produced vary depending on the type of diol. Examples of the monofunctional alcohol ROH include alcohols having 1 to 9 carbon atoms, and mixed alcohols thereof may also be used. The viscosity and plasticity of oligomers change depending on the type of alcohol. Butyl to hexyl alcohols are preferred. When the number of carbon atoms increases, the viscosity becomes high and the plasticity deteriorates. Therefore, the plasticizer of the present invention has a molecular weight of 430 to 1000,
The viscosity is preferably in the range of 20 to 600 cps,
The content of the bis compound in the complex ester and the molecular weight of the oligomer vary depending on the raw materials and conditions for production, but it is preferable to produce an ester containing mainly (more than half) the bis compound. In the reaction, a dealcohol transesterification catalyst such as tetrabutoxytitanium or alkyl titanate (polymer) is used, and divalent tin compounds such as tin diethylhexanoate have a coloring prevention effect, and these compounds may be used alone or in mixtures. That's good. Examples The evaluation as a plasticizer in the following examples is as follows:
Use vinyl chloride resin with an average molecular weight of 1300, and add 10 parts of tin-based stabilizer and calcium stearate to 100 parts by weight of the resin (hereinafter referred to as "parts").
After mixing 0.3 parts and 50 parts and 80 parts of plasticizer and kneading on a roll at 165°C for about 2 minutes, a sheet with a thickness of 1 mm was prepared, and the surface hardness and loss on heating were measured. The plasticization efficiency is determined by the measured average surface hardness of 50 parts and 80 parts of DOP, 87.8 and 78
is plotted with the number of copies on the horizontal axis and the hardness on the vertical axis, and 2
Plasticization efficiency was calculated by drawing a line parallel to the straight line connecting the points. In other words, find the average value of the distance from the measuring point of 50 parts and 80 parts of plasticizer to the same line as above, draw a parallel straight line, and take the amount of plasticizer that shows the same hardness as 50 parts of DOP as the plasticization efficiency. . Therefore, the lower the value, the better the plasticizing efficiency and the better the plasticity. Surface hardness was measured according to JIS6301. Examples 1 to 5 DOA and tripropylene glycol in molar ratios of 6:1, 4.7:1, 4:1, 3:1, respectively.
Mix at a ratio of 2:1, add 1g of tetrabutoxytitanium as a catalyst, and 2g of tetrabutoxytitanium as a cocatalyst to prevent coloring.
-0.5 g of tin ethylhexanoate was added to carry out transesterification. The reaction vessel was heated to 140 °C under a vacuum of 15 mmHg.
The reaction was carried out by heating and stirring at ~190° C. while recovering 2-ethylhequinol produced by the transesterification reaction. After the reaction is complete, add 5-10ml of water and heat to 100°C.
The catalyst was inactivated by stirring for 1 hour at
The mixture was treated at 1 mm under reduced pressure to remove unreacted DOA to obtain the desired complex ester. The average degree of polymerization n, solution viscosity, plasticization efficiency, and loss on heating of the obtained composite ester were as follows.

[Table] Note that cps is the measured value of centiboise at 21°C, and loss on heating is the loss on heating after heating at 160°C for 2 hours. Example 6, 7 DOA and dipropylene glycol 6 moles to 1
The mixture was mixed in a ratio of 2 moles to 1 mole and transesterified in the presence of 1 g of butyl titanate and 0.5 g of tin octylate. The same post-treatment as in the above example was performed to obtain a composite ester. The viscosity of the obtained composite ester was 72 cps and 112 cps, respectively, the plasticization efficiency was 46 and 48.5, and the loss on heating was 3.07.
%, 3.01%. Examples 8 and 9 Using a mixture of DOA and diethylene glycol at molar ratios of 5:1 and 3:1, transesterification was carried out while dealcoholization was carried out under reduced pressure in the same manner as in the previous example. Next, the same post-treatment as in the above example was performed to obtain a composite ester.
The viscosity of each composite ester obtained was 60 cps,
123cps, plasticization efficiency 45.5, 45, volatile loss 4.9
%, 2.1%. In Example 8, the volatilization loss was somewhat large, but the transesterification reaction was insufficient and the unreacted ester was
This is because it was not completely removed by vacuum distillation at 1 mmHg. Examples 10 and 11 Composite esters were obtained in the same manner as in the previous example, except that mixtures of DOA and 1.3-butanediol at molar ratios of 5:1 and 3:1 were used. The viscosity of each composite ester obtained was 65 cps,
102cps, plasticization efficiency is 43.2, 45.5, heating loss is
They were 1.37% and 1.09%. Example 12 A composite ester was obtained in the same manner as in the previous example except that a mixture of DOA and 1.4-butanediol at a molar ratio of 5:1 was used. The obtained composite ester had a viscosity of 89 cps, a plasticization efficiency of 50, and a loss on heating of 2.0%. Example 13 DOA and 1.6 hexanediol in a molar ratio of 5:1
A composite ester was obtained in the same manner as in the previous example, except that a mixture of esters and esters was used. The viscosity of the obtained composite ester was 93.8 cps, the plasticization efficiency was 45.5,
The loss on heating was 1.26%. Example 14 0.5 g of butyl titanate and 0.5 g of tin 2-ethylhexanoate were added to 2 moles of adipic acid and 6 moles of butanol, and a dehydration esterification reaction was carried out to give an acid value of 0.12. The butanol was removed under reduced pressure, then 0.5 mol of ethylene glycol (5:1 molar ratio of diol to dibutyl adipate) was added, and the butanol produced at 130-180°C was removed under a vacuum of 200 mm to 150 mm, and the distillate was The reaction was carried out until the calculated amount of butanol was distilled out, and finally the mixture was heated and stirred at 180°C and 18mmHg. Decatalyst and post-treatment were carried out by known methods, and then dibutyl adipate and a small amount of reaction intermediate were removed by distillation. The obtained composite ester had a viscosity of 29 cps, a plasticization efficiency of 42.5, and a loss on heating of 6.98%. The complex ester obtained by the above method was heated to 0.4 mmHg.
When distilled below, the boiling point is 225-230℃ and the viscosity is
A pure product of ethylene glycol bis dibutyl adipate, a complex ester obtained from ethylene glycol, butanol, and adipic acid, is obtained with a plasticization efficiency of 34.2 cps, a plasticization efficiency of 40, and a heating loss of 2.0%. A film was prepared using 50 parts by weight of this composite ester based on 100 parts by weight of vinyl chloride resin, and the low-temperature softening temperature was measured to be -31.6°C. The viscosity of the distillation residue is
112.4cps, n=2 containing solids with melting point 15-24℃,
It is a waxy ester containing 3, 4, and 5, and its plasticization efficiency is 46.5 and the loss on heating is 0.7%. Note that when the reaction ratio of ethylene glycol is increased, the resulting composite ester becomes a waxy substance containing solids. Example 15 Dibutyl adipate was produced by a dehydration esterification reaction, and after removing unreacted butanol by distillation, 1/5 molar amount of dipropylene glycol was added, and a transesterification reaction was carried out at 160 to 180°C under slight reduced pressure. Ivy. The obtained composite ester had a viscosity of 56.3 cps, a plasticization efficiency of 47.5, and a volatilization loss of 2.48%. The liquid obtained by distillation at 240-245°C/0.3 mmHg had a viscosity of 63.3 cps, a plasticization efficiency of 46, and a volatilization loss of 3.17%. Example 16 0.4 mol of 1.3-butanediol in 2 mol of dibutyl adipate (molar ratio of diester to diol 5)
Add 1) to 120-180℃ under mild vacuum (18mmHg).
The transesterification reaction was carried out by heating and stirring. The obtained composite ester has a viscosity of 46 cps, a plasticization efficiency of 37,
The loss on heating was 4.94%. The obtained complex ester was distilled under reduced pressure to give 239
The pure product of 1.3 butanediol bisbutyl diapate at ~243°C/0.5 mmHg had a viscosity of 55.3 cps, a plasticization efficiency of 40, and a loss on heating of 1.07%. What was obtained as a distillation residue was n=2 and 3,
It was a mixture of oligomers 4 and 5, with a viscosity of 153 cps and a plasticization efficiency of 43.5. Changing the molar ratio of the diester and diol, 3
The distillation residue of the complex ester obtained in mole to mole ratio has a viscosity of 240 cps and a plasticization efficiency of 45. Most of the 1.5 mol to 1 mol complex ester distillation residue has a high molecular weight, a viscosity of 308 cps, and a plasticizing efficiency.
It is 46.5. When the reaction molar ratio decreases in this manner, the molecular weight increases and the viscosity also increases, resulting in poor plasticization efficiency. In the case of adipic acid butyl ester, even if the reaction molar ratio is 1.5:1, the plasticization efficiency is
Better than DOP. At any of the above molar ratios, the loss on heating is 1% or less. Heat resistance test A film was made by kneading 50 parts by weight of the distilled complex ester (purified bis compound) with the above molar ratio of 5:1 to 100 parts by weight of vinyl chloride resin, and heated to 87°C.
The surface hardness was measured by heating in a hot air circulation heating furnace. Even after continuous heating for 8 weeks, the surface hardness did not reach 90, and the volatilization loss was less than 0.3%. On the other hand, when a similar film was made and tested using a conventional plasticizer, DOP showed that after 3 weeks,
The surface hardness reached a value of 90 or higher within 7 days for DBP and 10 days for DOA. Low-temperature properties The flexibility temperature (measured based on JIS K6745) of the film was -30.2°C. In contrast, the flexibility temperature of the material using DOP was -23.6°C. As described above, when the composite ester plasticizer of the present invention is used, heat resistance and low-temperature properties are significantly improved. Example 17 A composite ester was produced by transesterification in the same manner as in Example 1 using a mixture of dibutyl adipate and 1.6 hexanediol in a molar ratio of 5:1. The obtained composite ester had a viscosity of 59.1 cps, a plasticization efficiency of 45.2, and a loss on heating of 3.87%. Example 18 Butyl titanate was added to a mixture of dibutyl adipate and 1.2 propanediol in molar ratios of 5:1, 3:1, and 1.5:1 to carry out a transesterification reaction. The boiling point of the obtained complex ester (1.2 propanediol bisbutyl adipate pure product) is 230-240
℃/0.5mmHg, viscosity is 39cps, plasticization efficiency is 45
It was hot. The viscosity, plasticization efficiency, and heating loss of the oligomer in the distillation residue were as follows. Mixing ratio Viscosity Plasticization efficiency Heating loss (cps) (%) 5:1 194 48.5 2.6 3:1 279 53.8 1% or less 1.5:1 558.5 54.1 1% or less 8-week heat resistance test results showed no change in hardness and evaporation The weight loss was less than 0.3%. Example 19 Production of ethylene glycol bisadipate to produce complex ester via hydroxyethyl butyl adipate 0.5 g of butyl titanate as a dehydrated ester reaction catalyst was added to a mixture of 2.1 mol of adipic acid, 0.7 mol of ethylene glycol, and 2.1 mol of butanol.
Add 60 ml of toluene as an azeotropic solvent to carry out the dehydration esterification reaction, and the distillation rate of water removed is 30 ml.
At ~90%, 1.4 mol of butanol was added to react. After 14 hours, the acid value was 0.12. Next, after recovering toluene and butanol unreacted substances under reduced pressure, the temperature was reduced to 180°C under a reduced pressure of 100 to 18 mmHg.
The reaction was continued for about 4 hours while removing butanol. The obtained product had a viscosity of 42 cps and was a complex ester mainly composed of ethylene glycol bisbutyl adipate. By distillation, 57% by weight of bis compound was obtained. The distillation residue was an oil containing crystals. The plasticization efficiency of the distilled complex ester was 43, and the volatilization loss was 1.2%. Example 20 Using a mixture of 2.1 mol of adipic acid, 0.7 mol of 1.3-butanediol, and 0.7 mol of butanol, a dehydration esterification reaction was carried out in the same manner as in Example 19 while adding 2.1 mol of butanol. The reaction was carried out in the same manner as in Example 19 to prepare a complex ester mixture.
Obtained 285g. Its viscosity is 52cps, plasticization efficiency is
42, and the loss on heating was 1.8%. 52% by weight of bis compound was obtained by distillation.
Its softness temperature was -30.2°C. Example 21 Using a mixture of 2 mol of adipic acid, 1.0 mol of 1.2 propanediol and 0.5 mol of butanol, 2.5 mol was added dropwise during the reaction to carry out a dehydration esterification reaction in the same manner as in Example 19. After 14 hours, the acid value was 0.15. Add 1 mol of butyl adipate, which was prepared separately, to the reaction system, recover 0.2 mol of butanol under reduced pressure, and then heat the mixture at 180°C under reduced pressure of 200 to 18 mmHg.
A de-butanol transesterification reaction was performed to recover 0.8 mol of butanol. Post-treatment was carried out in the same manner as in Example 19, and dibutyl adipate was recovered by distillation.
A high boiling point composite ester of 230°C/0.4mm or more was obtained.
Its viscosity is 45 cps, plasticization efficiency is 42, and heating loss is
It was 1.1%. Effects of the Invention According to the present invention, by using a specific composite ester produced through a transesterification reaction as a plasticizer, the viscosity, plasticization efficiency, volatilization loss, and cold resistance are significantly improved compared to conventional plasticizers. Because of its excellent properties, its plasticity does not decrease even after the summer, and its mechanical strength does not decrease even in cold regions, making it suitable for use in agricultural greenhouses, etc. It has excellent effects as a soft plasticized resin molded product.

Claims (1)

[Claims] 1 General formula RO (CO(CH ₂ ) ₄ COOR'O) _o CO(CH ₂ ) ₄ COOR produced through transesterification (where n = an integer from 1 to 5, R is Carbon number 2-9
The alkyl group, R' represents a diol of a bifunctional alcohol having a main chain of 2 to 9 carbon atoms, or an alcohol residue of an ether alcohol) has a molecular weight of 430 to 1000 and a viscosity of 20 to 21°C. A plasticizer for vinyl chloride resin that uses a composite ester with a yield of 600 cps.