The world's current growth rate is about 1.14%, representing a doubling time of 61 years. We can expect the world's population of 6.5 billion to double by 2067 if current growth continues. By 2050, the world will host 9 billion people-if population growth slows in much of the developing world. The amount of arable land needed to feed them, however, will not increase at the same rate. As a result of urban growth, but also because of increased erosion and climate change, the amount of arable land is decreasing. The challenge is how to increase the intensity of agricultural activity while keeping the products affordable. Greenhouses that can be erected very inexpensively through the use of plastic film are one possible solution: They provide an ideal environment for plants, protect vegetables from the effects of frost, wind and rain, ensure uniformly high quality and help fruit ripen faster. In this way, several crops can be harvested in one year. Moreover, modern plastic film can be tailored specifically to the unique light and temperature requirements of many field-grown fruits. At the same time, they help to use water more economically - a resource that has to be looked after even more closely in the coming years. With the aid of such greenhouses, the output per hectare can be increased considerably. In 2009, about 900,000 tons of plastic film for greenhouses was produced worldwide, covering about 800,000 hectares of arable land, while demand for agricultural film for use in greenhouses is estimated to grow at 4% pa. The most important markets are found in the Mediterranean region. Other fast growing greenhouse areas in the world are Asia, South America and Eastern Africa. As per Victor Pacheo, BASF Schweiz, optimized agriculture also includes carefully considered use of agricultural chemicals to prevent harvests from attack by pests or mold. Environmentally friendly solutions are advancing on this front as well. The use of sulfur, for instance, being approved for application on organic produce even in highly regulated German agriculture, is recording noteworthy growth. However, the use of elemental sulfur and other agricultural chemicals places special demands on the film used in greenhouses. The reason for this lies in the sensitivity of thermoplastic films to UV light. This energy-rich radiation causes plastics to become brittle over the course of time via a complex, multi-step chemical mechanism. Low-cost, thin film in particular, can become useless after only a few weeks of exposure to the open sky as a result of this effect. Polymer chemistry has, of course, already developed additives that can slow this degradation reaction. However, their suitability for use in agricultural film is rather limited, since their effectiveness is reduced considerably by sulfur and acids stemming from the wooden or iron construction of greenhouses. Halogen-containing chemicals can also contribute to the deactivation of common UV stabilizers. A new light stabilizer developed by BASF can help improve these greenhouses and make them even more effective: Tinuvin® XT 200 protects film made from thermoplastic resins against overly fast degradation when exposed to UV light. This economical additive ensures the efficacy of these films over a longer period of time even in the presence of severe concentrations of agricultural chemicals like elemental sulfur. Thus it fills a gap in the BASF portfolio of light stabilizers for resins used in agriculture. There are, however, already alternatives in the BASF light stabilizer portfolio, specifically for the agricultural sector. Light stabilizers recommended depending on the amount of agricultural chemicals used are, for example, Tinuvin NOR 371, a powerful high-end product on the market since 2001, but also Tinuvin 494, Tinuvin 111 as well as Chimassorb® 2020 and 944. The new Tinuvin XT 200 operates in a range that for technical reasons cannot be served by Tinuvin 494 and for economic reasons cannot be served by Tinuvin NOR 371. This gap in the BASF-line of additives is now filled. Through use of Tinuvin XT 200 it is possible to produce in a very economical manner LDPE (Low-density polyethylene) films that withstand severe agricultural chemicals levels and also assure a service life of two and more years even under intense sunlight. The performance of such stabilized films is also very good when in contact with wood and metal greenhouse structures. Without a light stabilizer, they would not last even one growing cycle. NOR-HALS (Hindered amine based on alkoxyamine technology was first introduced by Ciba Specialty Chemicals (now BASF) around 2000 for PE agricultural film. Its low basic nature making it less susceptible to acidic additives of agrochemicals compared to conventional HALS. The basic deficiencies of NOR-HAL in terms of higher volatility, compatibility and lower thermal stability along with higher cost did not allow NOR-HALS to increase its market share of light stabilizer for agriculture market. PE grades for agriculture applications continue to use the traditional or conventional HALS. NOR-HALS requires to be developed further to eliminate its limitations in performance properties to achieve effective light stabilization & enhance resistance to pesticide. Clariant has developed an innovative light stabilizer specially targeted for use in agricultural films. This new molecule is designed to overcome the commercial and technical limitations of existing NOR -HALS products. This new light stabilizer is called Hostavin “HALS NOW”. It resists migration, improves thermal stability and offers greater compatibility with polyolefins. HALS has better light stability compared to UV absorbers and nickel quenchers in agricultural film applications. The reactive centers of HALS loses their efficacy in a detrimental environment. Researchers from Clariant separated the HALS base molecular structure into two sections: the substituent on the HALS nitrogen and the HALS part. Its substituent must not impact adversely the light stabilization in a hostile environment. Rankings of following different structures were determined for their effectiveness. They are: • Unsubstituted HALS: H = N-H • Alkyl substituted HALS: e.g. methyl = N-R • Acetyl substituted HALS: e.g. acetyl = N-CO -R • Alkoxy substituted HALS: e.g. propoxy = N-O-R This ranking shows that the sensitivity towards environmental stress from acids or sulphur-containing chemicals decreases from hydrogen to NOR. Clariant then neither worked on NOR group to develop the substitution of its alkyl group. With their experience with waxes and their use and behaviour in polymers, they focused on boosting the properties of the new stabilizer by choosing a suitable wax. The aim was to use a wax as a neither building block in order to overcome the neither existing drawbacks of NOR –HALS in respect of compatibility and thermal stability. Three different waxes with different thermal stability were selected. The wax with best thermal stability in NOR-HALS gave the best performance. Wax based on PE was better than that of PP. The researchers also found that low molecular weight HAL performed better than high molecular weight. For the HALS part of the molecule, it was determined. A new molecule of light stabilizer then was developed based on HALS and wax after optimizing the ratio of HALS/wax. It was named “HALS NOW”. HALS NOW has better compatibility with the matrix, allowing for highly loaded masterbatches. Loading with up to 70% HALS NOW did not lead to problems during processing or storage. An independent institute tested HALS NOW for phytotoxicity – the toxic effect that a compound can have on plant growth. It confirmed that under test conditions, HALS NOW does not affect the healthiness of the plants and that no increase of stress factors could be observed during exposure. Artificial weathering trials were carried out using HALS NOW, HALS and NOR HALS based film formulations treated pesticide. The standard HALS performed significantly worse than NOR HALS and HALS NOW. Further tests were carried out in 200 micron EVA films with different formulation based on 1.5% standard HALS, 1% NOR HALS LS 371, or 0.5-2.0% HALS NOW. In addition, 0.5% Benzophenone UV absorber was added to all films. In artificial weathering tests, the standard HALS was least effective, while HALS NOW outperformed even at lower dosage.