JPH078921B2 - Synthetic resin film - Google Patents

Description

TECHNICAL FIELD The present invention relates to a synthetic resin film, and more specifically to a synthetic resin film containing a fluorine-containing compound, particularly an agricultural synthetic resin film.

[Prior Art] In recent years, greenhouse cultivation has been performed in order to stably supply various vegetables and fruits throughout the year, and synthetic resin films such as polyvinyl chloride and polyethylene are widely used as covering materials for greenhouses. Has been done.

The original purpose of the greenhouse is to secure the temperature that is essential for the growth of cultivated crops, that is, to keep it warm. In order to improve this heat retention, it is necessary to improve the airtightness of the greenhouse and suppress the amount of heat that escapes by gap ventilation.

Recently, especially in the trend of energy saving, efforts have been made to increase the degree of airtightness of greenhouses as much as possible in order to effectively use solar energy within a range that does not adversely affect the crops in the house. However, as the degree of airtightness increases, the inside of the greenhouse tends to be humidified, resulting in a problem that the amount of fog generated in the greenhouse significantly increases.
Smoky is said to be closely related to the pest damage of cultivated crops or the quality of harvested crops, and is considered to be inevitable in greenhouse cultivation as much as possible.

The fog is basically caused by the condensation of water vapor in the greenhouse in the atmosphere in the greenhouse, and is a phenomenon that often occurs in the morning and evening when the temperature difference between the inside and outside of the greenhouse changes rapidly. Smoky can eliminate the ventilation of air inside and outside the greenhouse. However, in general, ventilation cannot be performed in many cases because importance is attached to the heat retaining property of the temperature, which has been a big problem in greenhouse cultivation.

Since the occurrence of fog is essentially a phenomenon caused by water in the greenhouse, it is possible to reduce the occurrence of fog by reducing the amount of water supplied to the atmosphere in the greenhouse. One of the measures against the occurrence of fog is to cover the soil surface in the greenhouse with multi-materials. However, the coating of multi-materials is not always an advantageous method for greenhouse growers because not only the covering work is complicated but also the material cost is heavy.

A method for improving a greenhouse covering material to reduce fog generation has also been proposed, and JP-A-55-91663 and JP-A-57-12070 disclose a method of adding a silicon-based surface active agent. Is disclosed. However, while the synthetic resin film containing these substances has a haze prevention effect,
There are drawbacks in that the adhesiveness between films, which is a necessary characteristic of a covering material, is poor, the drip-proof property is severely deteriorated, and the duration of the fog-preventing effect is poor.

JP-A-57-14648 and JP-A-59-93739 disclose
A method of adding a fluorinated sea surface active agent has been disclosed, but such a fluorinated sea surface active agent has a problem in the persistence of the fog-preventing effect and the drip-proofing effect even when added in a small amount.

[Problems to be Solved by the Invention] An object of the present invention is to provide a synthetic resin film which is particularly excellent in fog-preventing property and drip-proof property, and also has good weather resistance and film adhesiveness.

[Means for Solving Problems] The gist of the present invention is that a general formula: [In the formula, Rf is a fluorine-containing aliphatic group having 3 to 21 carbon atoms, R is a hydrogen atom or an aliphatic group having 1 to 3 carbon atoms, X is an iodine atom,
Bromine atom, chlorine atom or hydroxyl group, Y is sulfonic acid ester group or sulfuric acid ester group, a is 1 to 4, b
Is 2 to 3, and c is 2 to 100. ] It exists in the synthetic resin film characterized by containing the fluorine-containing compound shown by these.

Representative specific examples of the fluorine-containing compound (1X) are shown below: (However, in the composition of the fluorine-containing compounds of the compounds (2) and (3), the average of n is 3.6, 55 mol% of n = 3, 28 mol% of n = 4, and n = 5 11 mol% for n = 6, 5 mol% for n = 6, 1 mol% for n = 7
Is. ) The fluorine-containing compounds (1X) and (1Y) used in the present invention can be produced as follows.
Formula: RfCH _{2 a} Z [In the formula, Rf and a are as defined above, and Z is a sulfonate group, a sulfate group, an iodine atom, a bromine atom or a chlorine atom. ] The compound represented by [In the formula, R and b have the same meanings as described above. ] The ring-opening polymerization of the cyclic imino ether represented by Examples of the sulfonic acid ester group include a substituted alkane sulfonic acid group such as a trifluoromethane sulfonic acid group, a benzene sulfonic acid group, and a p-toluene sulfonic acid group, and an aromatic hydrocarbon sulfonic acid group. Examples thereof include monoalkyl sulfate groups such as monomethyl sulfate group and monoethyl sulfate group. By such ring-opening polymerization, when Z is a sulfonate group or a sulfate group, a fluorine-containing compound (1Y) is obtained,
When Z is a halogen atom, a fluorine-containing compound (1X) in which X is a halogen atom is obtained. To obtain a fluorine-containing compound (1X) in which X is a hydroxyl group, the polymer obtained by ring-opening polymerization may be reacted with an aqueous alkali solution.

In the ring-opening polymerization, the reaction molar ratio between the polymerization initiator and the cyclic imino ether can be arbitrarily changed, but usually monomer / polymerization initiator = 0.1 to 500. Polymerization temperature is 0-20
It is 0 ° C. As the solvent, aprotic solvents such as dimethylformamide and acetonitrile are preferable.
In the hydroxylation reaction, the concentration of the alkaline aqueous solution is usually 1 to 20% by weight. The amount of alkali used is in large excess with respect to the polymer obtained in the polymerization step. The reaction temperature is 10 to 50 ° C.

Examples of the synthetic resin that can be used in the present invention include ordinary synthetic resins such as polyvinyl chloride-based, polyolefin-based, acrylic resin-based, polyester-based, polyamide-based, etc., which are generally capable of forming a film, or a blend of the synthetic resins. . Among these, polyvinyl chloride-based and polyethylene-based resins are particularly preferable from the viewpoints of weather resistance, economy and light transmission. From the viewpoint of heat ray absorption, that is, heat retention of the house, polyvinyl chloride resin is most preferable. As the polyvinyl chloride resin, a homopolymer of vinyl chloride and a copolymer with vinyl acetate, ethylene, propylene, alkyl vinyl ether and the like can be used.

The synthetic resin film of the present invention preferably also contains a drip-proofing agent. As the dripproofing agent, any surfactant can be used as long as it can impart dripproofing properties to the synthetic resin film, and normally, a nonionic surfactant is preferably used. Specific examples of the nonionic surfactant include (A) ether type ones such as polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, and polyoxyethylene polyoxypropylene ether.
(B) Polyoxyethylene alkyl ester, ester type such as partial esterified product of polyhydric alcohol and fatty acid, (C) Amino ether type such as polyoxyethylene alkylamine, (D) Polyoxyethylene sorbitan fatty acid ester Examples thereof include ether ester type ones such as polyoxyethylene sorbitol fatty acid ester, polyoxyethylene mannitol fatty acid ester, polyoxyethylene glyceryl fatty acid ester, and polyoxyethylene propylene glycol monofatty acid ester. The selection of the nonionic surfactant can be basically made arbitrarily, but preferably, it has moldability, heat resistance, transparency and the like except that it maintains drip-proof property.
It is desirable to fully satisfy the performance as an agricultural coating material. Examples of suitable nonionic surfactants for obtaining the above properties include (i) polyhydric alcohols such as sorbitan, sorbitol, mannitol, mannitol, glycerin, and diglycerin, and a fatty acid moiety having 12 to 22 carbon atoms. Ester, (ii) the number of added moles of ethylene oxide or propylene oxide is 1 to 20, the polyhydric alcohol is sorbitan, sorbitol, mannitane, glycerin, diglycerin, and the polyoxyalkylene polyvalent in which the fatty acid has 12 to 22 carbon atoms Examples include alcohols, fatty acid esters, and mixtures of (iii) (i) (ii).

As other additives to be added to the synthetic resin film, commonly used plasticizers, stabilizers, lubricants, fillers, ultraviolet absorbers, antistatic agents, antioxidants, etc. can be used.
The present invention is not limited in any way.

The addition amount of the fluorine-containing compound (1X) or (1Y) is preferably 0.03 to 3.0 parts by weight with respect to 100 parts by weight of the synthetic resin. If it is less than 0.03 parts by weight, the haze-preventing effect and the drip-proofing effect are small.On the other hand, even if 3.0 parts by weight or more are added, the haze-preventing effect and the drip-proofing effect and their durability are not improved, and the weather resistance is rather lowered. Tend to do.

The antidrip agent is usually contained in an amount of preferably at least 0.5 part by weight, more preferably 1.0 to 5.0 parts by weight, based on 100 parts by weight of the synthetic resin. If the amount added is less than 0.5 part by weight, a sufficient drip-proofing effect cannot be obtained, and if it is 5.0 parts by weight or more, bleeding is large, whitening by water absorption tends to occur, and transparency tends to deteriorate, which is not preferable. However, the fluorine-containing compounds (1X) and (1Y) used in the present invention are 0.05% less than conventional ones.
Even if used in a small amount such as weight%, it is excellent in the fog-preventing effect and the drip-proofing effect and is effective even without using a drip-proofing agent.

[Effects of the Invention] As described above, the synthetic resin film of the present invention has a remarkable fog-preventing effect and a drip-proofing effect, and has excellent durability. Further, the fluorine-containing compound (1X) or (1Y), because it exerts the desired effect with the addition of a small amount, since there is almost no adverse effect on the adhesion between the films and the weather resistance, the synthetic resin film of the present invention, It has extremely high utility value as a covering material for agriculture.

[Examples] Next, the present invention will be described more specifically by showing Reference Examples, Examples and Comparative Examples.

Reference Example 1 (Synthesis of Compound (2)) In a test tube equipped with a magnetic stirrer and a three-way cock. (N is 3.63 on average) 1.14 g (1.62 mmol) A mixture of 1.60 g (16.1 mmol) and 5 ml of dimethylphonesimide was added, and the tube was sealed and kept at 100 ° C for 100 hours with stirring. Then, the reaction mixture was poured into 100 ml of a diethyl ether-hexane mixture (volume ratio 1/1), the precipitate was separated by decantation, dissolved in chloroform, and again the diethyl ether-hexane mixture having the same composition as described above was collected. Was added to cause precipitation, and the precipitate was dried under reduced pressure. A yellow waxy polymer was obtained.

The structure of the yellow waxy polymer is ¹ H-nuclear magnetic resonance analysis of the growth end onium salt, Met.

The yellow waxy polymer was placed in 20 ml of a 5% by weight aqueous sodium hydroxide solution and stirred at 20 ° C. for 30 minutes. Then, the organic matter was extracted with dichloromethane and dried under reduced pressure.

1.70 g (yield 64%) of the polymer represented by The molecular weight of the polymer was determined by the osmotic pressure method using chloroform as the solvent.
The result was 1665 measured at 40 ° C., and therefore the average number of repeating units q was 11.5.

Reference Example 2 (Synthesis of Compound (3)) In a test tube similar to Reference Example 1. (N is 3.63 on average) 1.11 g (1.62 mmol) A mixture of 0.74 g (10.2 mmol) and 10 ml of dimethylformamide was added, and the mixture was kept at 80 ° C for 40 hours in the same manner. After that, the reaction mixture was poured into 200 ml of a diethyl ether-hexane mixture having the same composition, and the same procedure was followed. 1.63 g (yield 88%) of the polymer represented by According to the permeation method, the molecular weight is 1750 and the average number of repeating units q is 15
Met.

Reference Example 3 (Synthesis of Compound (6)) 1.00 g (1.62 mmol) From a mixture of 0.14 g (1.64 mmol) and 10 ml of dimethylformamide 0.22 g (yield 23%) of the polymer represented by was obtained (molecular weight: 12
00, q: 6.2).

Examples 1 to 5 and Comparative Examples 1 to 7 The following basic composition was added and compounded with compounds of the types and amounts shown in Table 1 (parts by weight relative to 100 parts by weight of vinyl chloride resin) and calendered, A film with a thickness of 0.1 mm was produced.

The compounds added and compounded in the comparative example were as follows.

The obtained film was subjected to an anti-fog test, a drip-proof test, a weather resistance test and a film adhesion test, and evaluated according to the following criteria. The results are shown in Table 2.

Anti-combability evaluation method The film obtained in each Example and each Comparative Example was separately spread in a tunnel greenhouse with a frontage of 1 m, a height of 0.9 m, and a depth of 10 m, and the morning and evening smoky conditions were observed. It is evaluated according to the following criteria: ○: There is no fog □: There is a slight fog △: There is a large amount of fog ×: There is a large amount of fog Drip-proof property evaluation method It is observed with the naked eye and evaluated according to the following criteria: ○: Drip-proof property is very good □: Drip-proof property is good △: Drip-proof property is poor ×: Drip-proof property is very poor Weather resistance evaluation method Perform grid exposure outdoors , The deterioration of the film is visually observed and evaluated according to the following criteria: ○: No discoloration □: Discoloration is slightly observed △: Discoloration is observed in about half the area ×: Discoloration is remarkable on the entire surface Adhesion evaluation method Two films left in a greenhouse for 6 months after making the film Is adhered by a high-frequency sewing machine and pulled until the film is cut, and the adhesive strength is evaluated according to the following criteria: ◯: The adhesive part is not peeled at all, and the film is broken. Δ: The adhesive part is peeled by about half. Yes x: All the adhesive parts are peeled off. As can be seen from the results in Table 2, the film of the present invention is excellent in the fog-preventing property, the drip-proof property and their durability, and is also excellent in the weather resistance and the film adhesive property. It is a very useful synthetic resin film, especially an agricultural film.

Claims (2)

[Claims] 1. A general formula: [In the formula, Rf is a fluorine-containing aliphatic group having 3 to 21 carbon atoms, R is a hydrogen atom or an aliphatic group having 1 to 3 carbon atoms, X is an iodine atom,
Bromine atom, chlorine atom or hydroxyl group, Y is sulfonic acid ester group or sulfuric acid ester group, a is 1 to 4, b
Is 2 to 3, and c is 2 to 100. ] The synthetic resin film containing the fluorine-containing compound shown by these. 2. The synthetic resin film according to claim 1, which also contains a drip-proofing agent.