DE102008002423A1 - Use of polymethylmethacrylate-body (obtained by radical polymerization of composition comprising e.g. methylmethacrylate, plasticizers and active components e.g. methanol) as glazing materials for greenhouses for promoting plant growth - Google Patents

Abstract

Use of polymethylmethacrylate (PMMA)-body (obtained by radical polymerization of a composition comprising 88-95 wt.% of methylmethacrylate, 0-7 wt.% of plasticizer, 0.01-0.5 wt.% of hindered amine light stabilizers-compound, 0.03-0.10 wt.% of initiator and 0.1-10 wt.% of active components) as glazing materials for greenhouses for promoting plant growth, is claimed, where the active component is alcohol, water, vinyl compound and/or butyl lactate.

Description

The invention is concerned with the improvement of plant growth in greenhouses. In particular, the invention relates to the use of a PMMA body obtainable by radical polymerization of a composition comprising 88-95% by weight methyl methacrylate, 0-7% by weight plasticizers, 0.01-0.5% by weight HALS compound, 0.03-0.10% by weight Initiator and 0.1-10% by weight an active component.

PMMA (Polymethyl methacrylate) is produced today in large quantities and finds versatile use in professional as well as in hobby as a splinter-free and easy replacement for mineral Glass, z. B. as glazing, optical lens, roofing plate, Glazing in Gwächshäuser and the like more.

From the EP 0016870 are known based on methyl methacrylate plastics, which have a high transmittance for UV-A radiation (315-380 nm) and for UV-B radiation (280-315 nm). Their high UV transmission is maintained even with long-lasting exposure to radiation, if the plastics a small amount of a sterically hindered amine (so-called HALS compounds, as they are, for example, in the JP 0347,856 be described) is added. These capture radicals that form when exposed to radiation and otherwise destroy the plastic material slowly.

Also in the DE-OS 34 21 859 Plastics based on PMMA are described which contain sterically hindered amines and have high UV permeability.

The WO 99/25764 in turn, discloses the use of reducing phosphorus compounds to increase the UV transmission of PMMA-based moldings.

In the cited documents attention is drawn to the particular suitability of the respective PMMA material with increased UV transmission, ie excellent UV transmission, as a solarium material. This is primarily to be understood as the use of glazing material made of PMMA for covering solarium lamps. Secondarily, the couch materials themselves may consist entirely or partly of the so-called solarium material. True, in the WO 99/25764 also mentioned that the moldings can be used to advantage as UV-transparent cover in general, as an example and special purpose, however, is again called the use as a UV-transparent cover material for the application of sunbeds.

In practice, a material has proven particularly well so far as so-called solaria material, the material being sold under the trade name Plexiglas ^® GS 2458 by the company Röhm GmbH. This material is easy-care and well-permeable to tanning UV radiation.

The said material is for example from the technical information document of the company Degussa with the identification no. 222-6 (February 2002) as Plexiglas Sunactive ^® GS with the grades colorless 2458, colorless 2958 and colorless 2890 or from the technical information of the company Degussa with the identification no. 232-6 (April 2002) known as Plexiglas SUNACTIVE ^® XT Clear 24,770th Again, these writings have in common that as a field of application is lifted only on solar beds or sunbeds. This is z. B. apparent from the described advantages of the material, which is described as skin-friendly, hygienic and climate-resistant.

The same direction is aimed at WO 02/14388 A1 , which has an improved so-called solar bed material to the object. In particular, by the WO 02/14388 the well-known solar bed material Plexiglas ^® GS 2458 (commercial product of the company Röhm GmbH) further developed and by the addition of special additives with regard to the long-term stability of a uniform and high UV transmission, ie the reduction of yellowing of the material after long-term exposure to UV lamps, sunbeds and solar beds, further improved. Although it is referred to as a more general purpose as a glazing material, but there is no doubt from the overall context no other purpose of the improved material recognizable than that as a solarium material.

From the EP 0 324 940 A2 a plastic material with high UV transmission is known, consisting of a homo- or copolymers of 80 to 100 wt .-% Methylmethacrylateinheiten and up to 20 wt .-% units of at least one copolymerizable with methyl methacrylate comonomers, a UV stabilizer and optionally conventional additives , wherein the described material is characterized in that it contains as UV stabilizer 0.05 to 5 wt .-% of at least one organic peroxide having a half-life temperature for 10 h of at least 100 ° C. This type of UV stabilizer is essentially a polymeric peroxide formed by reaction of methyl methacrylate with oxygen. The decomposing only at high temperature polymeric peroxides to make a significant improvement in the UV stability of the PMMA possible and the partial replacement of HALS compounds. The plastic materials of the EP 0 324 940 A2 suitable as a cover for solariums, radiation equipment, lamps and greenhouses in the form of flat plates or in any shape after thermoforming.

Out the press release no. 2006/090 of the Rhenish Friedrich Wilhelms University Bonn is well-known that itself Harvest quality and yield of crops in greenhouses to increase significantly, if you have an antireflective solar glass in Connection with a Teflon-like film for covering greenhouses starts. The included in the disclosed composite roofing particularly transparent and UV-transparent special glass is a mineral glass, has a heat-insulating Effect and ensures that plants grow faster and make more flavorings.

At the mentioned composite of glass / foil material is hail security but only by the use of teflon-like composite film to ensure that the required hail security quite complex due to the combination with the expensive special foil has to be bought. Next to it is the transmission of mineral glass Also in the UV area still in need of improvement to the positive effect of UV-A and UV-B radiation on the growth of To use plants even better. That's the way it is difficult, young plants in the greenhouses to cure by UV light, the worse the UV yield is. The higher the yield of UV-A and / or UV-B radiation is, the sooner young plants can be exposed, so that, finally, the productivity of the greenhouse increases. In addition, it is important to accelerate plant growth and the formation of valuable flavorings in the plants too promote. This goal is better through realize an increased UV radiation yield. aim The present invention is therefore to find a material, which plant growth in greenhouses promotes and in particular a faster release of the Young plants through faster and easier climatic hardening allows. The cladding material should be stable and extremely weight-saving. At the same time that should Material be relatively hail.

A The object of the invention was also for known solar bedding material to develop new application areas based on PMMA.

These as well as others not specified in detail Tasks are performed by using all features of the claim 1 solved.

advantageous Embodiments are the subject of the dependent Claims.

in the Within the scope of the invention, it is now not without further notice The prior art has shown that the law elaborate glazing composite of mineral glass and teflon foil or Teflon-like film by a PMMA-based Solar couch or tanning material be substituted can, whereby both the hail security of the glazings receive remains as well as an excellent growth promoter of Plant is achievable.

• – wobei die aktive Komponente ausgewählt ist aus der Gruppe bestehend aus Alkoholen, Wasser, Vinylverbindungen, Butyllactat und einer Mischung aus zwei oder mehreren der vorgenannten Stoffe; und
• – wobei die Bestandteile der Zusammensetzung so gewählt sind, dass ihre Summe 100 Gew.-% ergibt.

The invention therefore provides the use of a PMMA body obtainable by radical polymerization of a composition comprising 88-95% by weight methyl methacrylate, 0-7% by weight plasticizers, 0.01-0.5% by weight HALS compound, 0.03-0.10% by weight Initiator and 0.1-10% by weight an active component, as glazing material for greenhouses to promote plant growth;

• - wherein the active component is selected from the group consisting of alcohols, water, vinyl compounds, butyl lactate and a mixture of two or more of the aforementioned substances; and
• - Wherein the components of the composition are chosen so that their sum is 100 wt .-%.

By the use according to the invention of a special PMMA-based material as a greenhouse cover will the sunlight required for photosynthesis increased, and the plant growth itself is accelerated. Particularly advantageous in the new use, however, is surprising the Effect on the formation of lycopene a red dye at z. B. tomato plants. Whose formation is at inventive Use particularly encouraged.

In addition, young plants are particularly hard-to-grow by the use according to the invention. Thus, one can either "seed" the young plants earlier or you can completely do without the hardening of the young plants by exposure to the outside. In this context, it should be noted that conventional Plexiglas ^® as well as mineral glass does not allow this effect.

In addition, the extremely good K values (thermal insulation values) of the PMMA-based cladding material to be used according to the invention allow a significant reduction in energy costs in greenhouses. Especially when used as double glazing or in the form of extruded hollow panels. Starting from a standard formulation, the PMMA bodies to be used according to the invention are obtained by adding alcohols, mixtures of alcohols and also water and / or further compounds to the monomer mixtures of the standard formulation. In the following formulation, the particular compound used or a mixture of the compounds is referred to as the active component. The standard formulation, including the active component, includes: 88-95% by weight methyl methacrylate, 0-7% by weight plasticizers, 0.01-0.5% by weight HALS compound, 0.03-0.10% by weight Initiator and 0.1-10% by weight an active component,

When Alcohols are monohydric or polyhydric C1-C10 alcohols in question, which can also be branched. A functional one Variation of the invention is characterized in that PMMA body be used, the molding composition as the active component as alcohol Methanol, ethanol, propanol, isopropanol, n-butanol, sec-butanol, tert-butanol or pentanols singly or in mixtures of two or more.

A Further improvement can be achieved through the use of additional compounds be achieved, such. As vinyl compounds, butyl lactate and siloxanes and mixtures of the abovementioned compounds, the two or have more components of the aforementioned compounds.

Particularly useful is the use of vinyl compounds in the form of vinyl acetate or compounds of the formula I. C (R ¹ R ² R ³ ) - (C = O) -O-CH = CH ₂ (formula I), wherein R ¹ , R ² and R ^{3 are} linear or branched alkyl radicals having one to six carbon atoms, wherein at least one of R ¹ , R ² and R ^{3 is} a methyl radical and wherein the total number of carbon atoms in the radicals R ¹ , R ² and R ^{3 is} nine, ten or eleven. Such compounds are available, for example, under the name VeoVa9 (9 carbon atoms, R ¹ -R ³ ) or VeoVa11 from Shell Chemicals.

The Alcohols, alcohol mixtures or other active components in amounts of 0.1 to 10 wt .-% added to the monomer mixture. Preference is given to contents of from 0.2 to 8% by weight of active components, Levels of from 0.2 to 6% by weight of active compounds are particularly preferred Components.

The monomer mixture consists of 88-95 wt .-% of methyl methacrylate, preferred are 90-95 wt .-% of methyl methacrylate, very particularly preferred are 92-94.5 wt .-% of methyl methacrylate. A standard formulation, as used in the invention, wherein the active component is added, is composed, for example, as follows:
93.85 parts by weight of methyl methacrylate,
6% by weight of acetyltributyl citrate (as plasticizer) Citrofol B2 (from Jungbunzlauer),
0.1% by weight of Tinuvin 770 (as HALS) (Ciba); and
0.05% by weight of initiator.

The initiator used may be the initiators customary in cast polymerization and / or bulk polymerization with subsequent extrusion. Further valuable information is obtained z. In H. Rauch-Puntigam, Th. Völker in "Acrylic and Methacrylic Compounds", Springer-Verlag 1967 ; Houben-Weyl, 4th ed., Volume XIV / 1, Macromolecular substances, Part 1. S. 1010-1078, Georg Thieme Verlag 1961 ).

When Plasticizers may preferably acetyl butyl citrate and / or Trieethyl citrate can be used. It may also be preferred to dispense with the plasticizer.

The described polymerization compositions and polymers or molding compounds are known per se to PMMA bodies or PMMA-based bodies. Such is the polymerization after the chamber process with simultaneous shaping possible, as well as the production of molding material and subsequent Extrusion of the molding composition is practical as a shaping step. Either the production of cast glass as well as the production of extruded glass are methods familiar to the person skilled in the art.

The Use according to the invention of PMMA bodies To increase plant growth can generally be used as cladding material done for greenhouses. A preferred use according to the invention provides the use as roofing material for greenhouses in front.

A Another preferred use is the use of PMMA body as wallcovering material in greenhouses. Particularly favorable results in the increase of plant growth and the hardening of young plants can be achieved by the combined use as roofing and wall cladding material in greenhouses.

in this connection can in principle be arbitrarily shaped PMMA bodies be used. Particularly favorable PMMA body in the form of plates. These are functional massive and are made of cast glass. Alternatively, can be with special Success also use weight-saving hollow chamber panels. These are suitably made of extruded glass, so-called XT-glass. Here, the plates can be two or more straps and a larger number vertically between the Belts extending webs to form a plurality of hollow chambers in the plates. Even more preferred are so-called truss plates, where there are vertical and sloping webs. Thus, a much better stabilization of the plates is possible.

After all You can also PMMA body in the sense of Use invention, which in the form of injection-molded material available.

in the Below, the invention is based on embodiments explained in more detail.

To be used according to the invention PMMA bodies in the form of plates can, for. For example following are produced: the standard recipe and the mixtures of active compounds are intimately mixed, in glass chambers, sealed with a profile cord made of PVC, filled and in a water bath, for example, according to a temperature-time profile polymerized, the 6 to 7 h at 46 ° C, 15 h at 40 ° C. and 4 h at 100 ° C.

To the first stage of polymerization, the profile cord is removed. After the second polymerization stage, the final polymerization takes place at elevated temperature. Optionally, again at elevated temperature (160 ° C) are annealed.

The obtained PMMA plate (eg 1000 × 300 × 8 mm) is cut to the desired size. After the general production process, PMMA sheets having the following composition were produced: Colorless 2 mm g / 100 kg batch CITROFOL B II 5,500.00 Tinuvin 770 DF (PARA) 100 Peroxan AZDN 22 butyl 300 Baysolvex D2EHPA 3 Alcohol mixture 9.9% methanol and 90.1% ethanol 300 MMA (loose parachemia) 93775.00 Colorless 2.5 mm g / 100 kg batch MMA (loose parachemia) 95268.00 CITROFOL B II 4,000.00 Tinuvin 770 DF (PARA) 100 Peroxan AZDN 22 butyl 300 Alcohol mixture 9.9% methanol 90 and 1% ethanol 300 MAS solution 50% 8th Baysolvex D2EHPA 2 Example 1: Colorless 3 mm g / 100 kg batch CITROFOL B II 4,500.00 Tinuvin 770 DF (PARA) 100 Peroxan AZDN 19 butyl 300 Alcohol mixture 9.9% methanol and 90.1% ethanol 300 Baysolvex D2EHPA 3 MAS solution 50% 10 MMA (loose parachemia) 94768.00 Example 2: Colorless 4 mm g / 100 kg batch CITROFOL B II 4,000.00 Tinuvin 770 DF (PARA) 100 V 69 (TERT-BUTYL-2-ETHYLHEXANOATE) 36 GAMMA TERPINES 1 butyl 300 Alcohol mixture 9.9% methanol and 90.1% ethanol 300 MMA (loose parachemia) 95263.00 Example 3: Colorless 5 mm g / 100 kg batch V 69 (TERT-BUTYL-2-ETHYLHEXANOATE) 36 CITROFOL B II 4,500.00 Tinuvin 770 DF (PARA) 100 butyl 300 Alcohol mixture 9.9% methanol and 90.1% ethanol 300 MMA (loose parachemia) 94764.00 Colorless 6 mm g / 100 kg batch CITROFOL B II 4,500.00 Tinuvin 770 DF (PARA) 100 V 69 (TERT-BUTYL-2-ETHYLHEXANOATE) 25 MAS solution 50% 5 butyl 450 Alcohol mixture 9.9% methanol 90.1% ethanol 450 MMA (loose parachemia) 94470.00 Example 4: Colorless 8 mm g / 100 kg batch Tinuvin 770 DF (PARA) 100 CITROFOL B II 4,500.00 V 73 (tert-butyl perbenzoate) 1 V 69 (TERT-BUTYL-2-ETHYLHEXANOATE) 20 butyl 500 Bisomer EGDMA 20 Alcohol mixture 9.9% methanol and 90.1% ethanol 500 MMA (loose parachemia) 94281.00 MAS solution 50% 72 Baysolvex D2EHPA 4 GAMMA TERPINES 2

MMA

= Methylmethacrylat;

CITROFOLL B II

= Acetyltributylcitrat, Weichmacher des Herstellers Jungbunzlauer;

Tinuvin 770 DF

= Bis(2,2,6,6-tetramethyl-4-piperidyl)sebacat, HALS der Fa. CIBA;

Peroxan AZDN

= 2,2'-Dimethyl-2,2'-azodipropionitril, Reaktionsinititator der Fa. Pergan GmbH, Bocholt;

Baysolvex D2EHPA

= Di-(2-ethylhexyl)-phosphorsäure der Fa. Lanxess;

MAS-Lösung 50%

= Methacrylsäure 50%ige Lösung;

V69

= tert-Butyl-2-ethylhexanoat

gamma-Terpinen

= 1-Isopropyl-4-methyl-1,4-cyclohexadien;

V73

= tert-Butylperbenzoat;

Bisomer EGDMA

= Ethylenglycoldimethacrylat;

The abbreviations used in the example formulations 1-4 stand for:

MMA

= Methyl methacrylate;

CITROFOLL B II

= Acetyltributyl citrate, plasticizer of the manufacturer Jungbunzlauer;

Tinuvin 770 DF

= Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, HALS from CIBA;

Peroxan AZDN

= 2,2'-dimethyl-2,2'-azodipropionitrile, reaction initiator from the company Pergan GmbH, Bocholt;

Baysolvex D2EHPA

= Di- (2-ethylhexyl) -phosphoric acid from the company Lanxess;

MAS solution 50%

= Methacrylic acid 50% solution;

V69

= tert-butyl 2-ethylhexanoate

gamma-terpinene

= 1-isopropyl-4-methyl-1,4-cyclohexadiene;

V73

= tert-butyl perbenzoate;

Bisomer EGDMA

= Ethylene glycol dimethacrylate;

to Determination of the UV transmission of the plates from the examples 1-7 was outdoors under changing irradiation conditions measured with a portable light meter of the "optometer" type. The radiation passing through the sample plate was in a Distance measured from 32 mm (distance measuring head to the lower edge of Plate). As a reference, a parallel measurement was carried out at the same time measured without PMMA plate for control. The one for the passed Radiation of a plate was added to the respective control (without plate) in relation (normalized). The quotient from the radiation passing through the plate, and the for the control sample (without plate) measured radiation leaves a statement about the permeability the respective plates for a given spectral component to.

• • Abstand Messkopf zur unteren Kante der Plexiglasscheibe: 32 mm
• • Die Messungen jeweils einer Platte wurden zeitgleich mit einer unbedeckten Kontrolle als Referenzwert gemessen.
• • Gemessen wurde im Freien unter wechselnden Einstrahlungsverhältnissen.

The results of the measurements are summarized in the following table: example 1 UVA [W / m ² ] UVB [W / m ² ] PAR [E / m ² ] 1st Wdh. control 14.07 0.33 371.50 colorless, 3 mm no. 1 12.72 0.29 343.58 % Plexiglas to control 90.41 87.88 92.48 2nd Wdh. control 15.89 0.37 466.42 colorless, 3 mm no. 2 14.42 0.32 427.85 % Plexiglas to control 90.75 86.49 91.73 Example 2 UVA [W / m ² ] UVB [W / m ² ] PAR [E / m ² ] 1st Wdh. control 16.59 0.37 529.32 colorless, 4 mm no. 1 15,01 0.32 494.05 % Plexiglas to control 90.48 86.49 93.34 2nd Wdh. control 19,80 0.41 730.23 colorless, 4 mm no. 2 17.62 0.36 685.84 % Plexiglas to control 88.99 87.80 93.92 Example 3 UVA [W / m ² ] UVB [W / m ² ] PAR [E / m ² ] 1st Wdh. control 15.84 0.36 533.86 colorless, 5 mm no. 1 14.33 0.30 502.98 % Plexiglas to control 90.47 83.33 94.22 2nd Wdh. control 15.90 0.35 547.55 colorless, 5 mm no. 2 14.35 0.30 514.71 % Plexiglas to control 90.25 85.71 94.00 Example 4 UVA [W / m ² ] UVB [W / m ² ] PAR [E / m ² ] 1st Wdh. control 16.30 0.35 583.68 colorless, 8 mm no. 1 14.61 0.29 548.41 % Plexiglas to control 89.63 82.86 93.96 2nd Wdh. control 16.25 0.34 630.17 colorless, 8 mm no. 2 14.56 0.28 584.57 % Plexiglas to control 89.60 82.35 92.76

• • Distance measuring head to the lower edge of the Plexiglas pane: 32 mm
• • The measurements of one plate were measured simultaneously with an uncovered control as a reference value.
• • Measurements were taken outdoors under changing irradiation conditions.

by virtue of From the measurement results you can see that the colorless types both in the UVA as well as in the UVB range, an only insignificant reduction the permeability compared to the control measurement experiences.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• EP 0016870 [0003]
• JP 0347856 [0003]
• - DE 3421859 [0004]
• WO 99/25764 [0005, 0006]
• WO 02/14388 A1 [0009]
• WO 02/14388 [0009]
• - EP 0324940 A2 [0010, 0010]

Cited non-patent literature

• - H. Rauch-Puntigam, Th. Völker in "Acrylic and Methacrylic Compounds", Springer-Verlag 1967 [0026]
• - Houben-Weyl, 4th edition, Volume XIV / 1, Macromolecular substances, Part 1. pp. 1010-1078, Georg Thieme Verlag 1961 [0026]

Claims (9)

Use of a PMMA body obtainable by radical polymerization of a composition comprising 88-95% by weight methyl methacrylate, 0-7% by weight plasticizers, 0.01-0.5% by weight HALS compound, 0.03-0.10% by weight Initiator and 0.1-10% by weight an active component, as glazing material for greenhouses to promote plant growth; - wherein the active component is selected from the group consisting of alcohols, water, vinyl compounds, butyl lactate and a mixture of two or more of the aforementioned substances and - wherein the constituents of the composition are selected so that their sum is 100 wt .-%. Use according to claim 1, characterized methanol, ethanol, propanol, isopropanol, n-butanol, sec-butanol, tert-butanol or pentanols individually or in mixtures used by two or more. Use according to claim 2, characterized in that vinyl acetate or compounds of the formula I as vinyl compounds C (R ¹ R ² R ³ ) - (C =O) -O-CH = CH ₂ (Formula I) wherein R ¹ , R ² and R ^{3 are} linear or branched alkyl radicals having one to six carbon atoms, wherein at least one of R ¹ , R ² and R ^{3 is} a methyl radical and wherein the total number of carbon atoms in the radicals R ¹ , R ² and R ^{3 is} nine, ten or eleven. Use according to one of the preceding claims as roofing material for greenhouses. Use according to one of claims 1 to 3 as wall covering material for greenhouses. Use according to one of the preceding claims of PMMA bodies in the form of plates. Use according to claim 7 in the form of extruded Plates. Use according to claim 7 in the form of cast glass. Use according to claim 8 in the form of injection-molded Material.