Sun protection for greenhouses

After six years of research, BASF will launch at the K fair a new stabilizer of light which is capable of improving the greenhouses and make them more effective: Tinuvin XT 200 protects films made with resins termo-plásticas against the rapid overall degradation suffered when exposed to ultraviolet rays. This economic additive ensures the effectiveness of the films for a longer time period, even when there are serious agricultural chemical agents, such as the elemental sulphur concentrations. Thus, Tinuvin XT 200 filled the void that existed in the portfolio of BASF of stabilizers of light to resins used in the agricultural sector.

As a result of urban development, and also due to the increased erosion and climate change, the area of arable land has been reduced. Currently, the challenge is to boost agriculture and at the same time, maintain affordable prices of product. Greenhouses can be constructed without major costs through the use of plastic films and are one of the possible solutions to this problem. They offer an ideal environment for plants, protecting vegetables from the effects of frost, wind and rain, and guaranteeing a high uniform quality, as well as contributing to the more rapid maturation of fruit, allowing multiple crops in a year. On the other hand, the current plastic film can be adapted to the specific measure of the individual requirements of light and temperature of many fruit grown in the field. At the same time, it helps to reduce the consumption of water, a resource that should take care more and more in years to come.

The advantages of greenhouse production are so convincing that vegetables such as tomatoes, peppers, cucumbers and aubergines are already grown under roofs of polyolefin. In 2009, the world production of thermoplastic films for greenhouses amounted to about 900,000 tonnes and occupied an area of 800,000 hectares arable land - surface or, roughly, to the sum of the extensions that occupy the cities of TokyoMexico City, Madrid, Johannesburg, Rome, Moscow and Berlin--at the same time, is expected to demand for films for agriculture which are used in greenhouses to increase at an estimated annual rate of 4%. The most important markets are found in the Mediterranean area. Other areas of rapid growth in demand for greenhouses worldwide are Asia, South America and East Africa.

Optimized agriculture also includes the use of chemical agents carefully selected, so that mold and pests attack crops. In this field, is being also achieved great progress in environmentally friendly solutions with the environment. The use of sulfur as whose application in organic products has been approved even in highly regulated as the German Agriculture, is experiencing a remarkable growth. However, the use of elemental sulfur and other chemical agents in agriculture requires that films for agricultural use, which are used in greenhouses meet some special characteristics.

The reason lies in the sensitivity of thermoplastic films to UV light. This radiation, rich in energy, causes that plastics become brittle over time, because of a complex chemical process in multiple steps. Because of this low cost, in particular the finest films can be useless after only some weeks of exposure to conditions of open sky. Of course, the chemistry of polymers has already developed additives that can slow this reaction of degradation. However, their suitability for employment in films for agricultural use is rather limited, as its effectiveness is reduced significantly under the effect of the Mishraq and acids that emanate from the constructions of wood or iron of greenhouses. Halogen-containing chemical agents also contribute to the deactivation of the common stabilizers of UV rays.

However, there are alternatives in the portfolio of BASF light stabilizers specifically developed for the agricultural sector. Light stabilizers recommended under the amount of chemical agents for agriculture which are used are for example: Tinuvin NOR 371, a powerful product of high range available in the market since 2001; Tinuvin 494 and Tinuvin 111, as well as Chimassorb 2020 and 944. The new Tinuvin XT 200 is used in fields in which, for technical reasons, can not stock up using Tinuvin 494 or for economic reasons can not stock up with Tinuvin NOR 371. In this way, has covered the gap in the line of additives of BASF.

The use of Tinuvin XT 200 makes very economical way to produce films LDPE (low density polyethylene) that resist high levels of chemical agents of agricultural use and at the same time ensuring a life of service of two years or moreeven in bright sunlight conditions intense. The performance of these stabilized films is also very good when they come into contact with the structures of wood and metal of the greenhouses. Without a stabilizer of light, would not last nor a crop cycle.

The properties of the new stabilizer of UV rays have been tested for years, through exhaustive trials at Ciba/BASF. These trials have been made not only in highly specialised laboratories, but also in experimental greenhouses in great development center of stabilizers of light for the agricultural use of BASF in Bologna (Italy).

After the thorough investigation in the laboratory of the characteristics of aging of the stabilized film, also found his performance in exhaustive field in Italy and Spain tests. Now the new stabilizer has the opportunity to grow to the rhythm of a dynamic market.