JPS6049731A - Artificial soil for hydroponic culture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to artificial soil for hydroponic cultivation of plants. More specifically, the present invention provides artificial soil suitable for hydroponic cultivation that is made of a water-swellable gel-like polymer whose main components are (meth)acrylamide component units and crosslinkable monomer component units. be.

Traditionally, hydroponic cultivation of plants involves cultivating plants directly in water containing fertilizer components, or cultivating plants in artificial soil filled with pebbles, gravel, glass pieces, plastic, etc. in water containing dissolved fertilizer components. There are methods to do this.

The former method does not adequately retain the roots during hydroponic cultivation, so there are drawbacks such as floating roots, overturning of plants, settling, and poor ventilation. Even if it is possible to retain water, the water retention is not sufficient, and it is not excellent from an aesthetic point of view, so it is difficult to say that it is suitable for ornamental hydroponic cultivation, and in this case, it is not suitable for root ornamentation.

The present inventors have developed a composition comprising a water-swellable gel-like polymer consisting of a crosslinked copolymer whose main components are a (meth)acrylamide component unit and a crosslinkable monomer component unit, and an organotin compound. When used as artificial soil for hydroponic cultivation, it has much better transparency, water retention, root retention, air retention, ornamental properties, etc. than the conventional artificial soil mentioned above, and it also has anti-algae and anti-algae properties. The present invention was achieved based on the discovery that transparency and ornamentability do not deteriorate over a long period of time due to excellent mold resistance.

That is, the present invention comprises [A] a water-swellable gel polymer consisting of a crosslinked copolymer whose main constituents are (meth)acrylamides component units and crosslinkable monomer component units; and (B) an organotin component unit. This is an artificial soil for hydroponic cultivation consisting of compounds.

The water-swellable gel polymer used in the artificial soil for hydroponic cultivation of the present invention is a crosslinked copolymer whose main components are (meth)acrylamide component units and crosslinkable monomer component units. . The crosslinked polymer has a (meth)acrylamide component unit and a crosslinkable monomer component unit as essential main components, but it also contains a small amount, for example, 10 mol% or less of other copolymers. There is no problem even if it contains ingredients. Examples of the other copolymerization components include component units such as acrylic acid, methacrylic acid, salts of acrylic acid, and salts of methacrylic acid. Here, the (meth)acrylamides component unit is acrylamide, methacrylamide, or an N-alkyl substituted product thereof, and specifically, acrylamide, methacrylamide, N-methylacrylamide, NJ-dimethylacrylamide, N-methylmethacrylamide. Examples include amide, N,N-dimethyl(meth)acrylamide, and the like. Among these (meth)acrylamide component units, acrylamide or methacrylamide component units are particularly preferred. Further, specific examples of the crosslinkable monomer component unit include N,N'-methylenebis(meth)acrylamide, N,N'-ethylenebis(meth)acrylamide,
N, N'-ethylidene bis(meth)acrylamide, N
, N'-propylene bis(meth)acrylamide, N,
Ni fluoropylidene bis(meth)acrylamide, N,
N4 hexamethylene bis(meth)acrylamide, N,
Bis(meth)acrylamides such as N'-phenylene bis(meth)acrylamide, bis(meth)acrylates such as ethylene bis(meth)acrylate, propylene bis(meth)acrylate, hexamethylene bis(meth)acrylate, diethylene glycol Bis(meth)acrylate, triethylene glycol bis(meth)
Examples include acrylate and voluteylene glycol bis(meth)acrylate, and a mixture of two or more components is also acceptable.

Among these crosslinkable monomer component units, N,N-methylenebis(meth)acrylamide component units are particularly preferred. The content ratio of the crosslinkable monomer component unit is usually 0.01 to 10 mol%, preferably 0.01 to 10 mol%. The range is from 5% to 5% by mole.

The water-swellable gel polymer may be a crosslinked copolymer composed of (meth)acrylamide component units and crosslinkable monomer component units, which are the essential constituents, It may also be a crosslinked copolymer composed of a class component unit, a crosslinkable monomer component unit, and the other copolymerizable monomer component units. Among the water-swellable gel polymers, the latter terpolymer can be produced by a direct copolymerization method, or by partially hydrolyzing or saponifying the former binary copolymer. It can also be produced by a method of converting a part of the (meth)acrylamides component units into (meth)acrylic acid or salt component units.

The density of the water-swellable gel-like polymer is such that the copolymer is
The value after drying at C for 48 hours is 1.0 to 1.
8g/cta, preferably 1.1 to 1.5g/c+
+! The degree of swelling in water at 24° C. is usually in the range of 3 to 5 based on the weight ratio of water absorbed to the dry polymer.
000, preferably in the range of 8 to 1000. The density and degree of swelling of the dried polymer were measured using the following method.

(1) Density; constant weight (-g) of dry polymer is 25
The sample was collected in a ml vicinometer. The pycnometer containing the polymer was then placed in a constant temperature bath at 24°C and filled with toluene at 24°C. The toluene volume (V) was determined from the toluene weight required for this, and calculated using the following formula.

Polymer density (g/cJ) = -25-■ (2) Swelling degree: A certain weight (Wlg) of the dried polymer was collected and immersed in water for 24 hours at 24 degrees to sufficiently swell the polymer. . Thereafter, excess water was removed and the weight (W, +g) of the swellable gel was measured and calculated using the following formula.

1. The organotin compound CB) blended into the artificial soil for hydroponic cultivation of the present invention is a tin compound having at least N [lil hydrocarbon group, specifically tetramethyltin, tetraethyltin, tetra-n -butyltin, tetraoctyltin, tetraethyltin, dimethyllegioctyltin, trimethyltin chloride, triethyltin bromide, tributyltin chloride, trioctyltin chloride, triphenyltin chloride, trimethyltin acetate,
Tributyltin propionate, trioctyltin laurate, diethyltin dichloride, dibutyltin tribromide, dioctyltin difluoride, dibutyltin diacetate, dioctyltin diphosphate, dimethyltin oxide, di-n-octyltin oxide, Dibutyltin maleate, bis(monobutylmaleate) dioctyltin, engineered 2-ethylhexyl tayiki, hexamethyldistanoxane, hexaphnyldistannoxane, hexapropyldistannoxanenyldistannoxane, trimethyltin fluoroborate , trimethyltin fluoroborate, tripropyltin fluoroborate, triphenyltin fluoroboret 1, and the like.

The blending ratio of the organic tin compound is usually 0.1 to 1000 ppm, preferably 1
The range is from 500 ppm to 500 ppm. As a blending method, the crosslinked copolymer may be swollen in water containing the organotin compound, or the organotin compound may be added to the crosslinked copolymer swollen with water.

The artificial soil for hydroponic cultivation of the present invention expands the copolymer in water.
It is used in a moist state, and if necessary, mildewproofing agents and water are added to the water.
Other algaecides and fertilizer components, such as Hoagland's solution, can also be dissolved.

Further, in some cases, the coloring agent may be melted to enhance the ornamental effect. Into the artificial soil for hydroponic cultivation of the present invention, grown plants can be transplanted, seedlings can be transplanted, and seeds can be sown. The artificial soil for hydroponic cultivation of the present invention has transparency, air preservability,
It is suitable for ornamental cultivation because it has excellent water retention and root retention, and it is also suitable for experimental observation cultivation because the growth status of roots can be observed. For these uses, it is suitable to cultivate in transparent pots or containers made of glass, polystyrene, polymethyl methacrylate, polyolefin, or the like.

Example 1 Dry pellet shape (cylindrical shape with diameter of 2 cranes and length of 21 m)
Acrylamide N. 10 g of N-methylenebisacrylamide (100:1) copolymer, 200 ml of water, 0.21 g of Hoagland's fertilizer and 1.0 g of tributyltin chloride. OO
+ng was added and left overnight to swell the copolymer to create artificial soil for hydroponic cultivation. A Saintpaulia plant with a plant height of approximately 100 cm, which had been grown by alley cultivation, was transplanted into this artificial soil, placed in a room exposed to sunlight, and cultivated while supplementing with dilute liquid fertilizer. Saintpaulia grew smoothly, and even after four months, the artificial soil remained clear and colorless.

Comparative Example 1 In Example 1, when the same operation as in Example 1 was performed without adding tributyltin chloride, unicellular algae began to proliferate after about one month, and the artificial soil began to take on a green color. Although no abnormality was observed in the growth of Saintpaulia, after four months the entire artificial soil was covered with green algae and became opaque.

Example 2 The same operations as in Example 1 were performed except that Begonia was transplanted instead of Saintpaulia.

As a result, the begonias grew smoothly as in Example 1.
In addition, even after 4 months, in artificial comparative example 2 and example 2, tributyltin chloride was not added.
Begonias were transplanted in the same manner as in Example 2.

As a result, brown algae began to appear after about one month, and four months later, although there was no abnormality in the growth of hegonia, brown algae grew throughout the artificial soil, making it opaque.

Examples 3-6

Claims (1)

[Scope of Claims] <11 (A) A water-swellable gel-like polymer consisting of a crosslinked copolymer whose main components are (meth)acrylamide frequent component units and crosslinkable monomer component units, and CB) Artificial soil for hydroponic cultivation consisting of an organic tin compound.