1: исправьте предложения на основе текста. 1. the metals can be alloyed but the polymers cannot. 2. it is impossible to develop polymeric substances with the scheduled properties. 3. the so-called "aging" of the polymers is due to chemical and physical changes caused only by temperature. 2. ответьте на вопросы письменно. 1. what are polymers characterized by? 2. what do the properties of the polymers depend on? 3. what is the main concern of the геsearches and engineers? 3. переведите письменно на язык, используя текст. 1. полимеры широко используются в промышленности. 2. на полимеры влияет свет, тепло и влажность. 3. основная ученых и инженеров – улучшить качество полимеров. текст: synthetic polymers and their application polymers are the dynamic part of industry, particularly plastics and fibres. a polymer is a substance consisting of molecules and characterized by its viscosity colour and by its softening points. until recently it was thought that the properties of the polymers were determined only by the chemical structure of their molecules. chemists after many years of research have established that the properties of polymers produced are largely determined by the pattern of their big molecules. the properties of polymers depend on their super-molecular structure. polymers just like metals can be alloyed, i.e. groups different in composition may be introduced into the structure of the polymers. a study has been made of possible variants of structural patterns of different polymers and of ways of developing the required structures. this has opened up the possibility for developing substances with scheduled properties. high molecular compounds possessing a great variety of valuable properties, they can therefore be used in a wide range of things. the main concern of researchers and engineers is to improve the quality of mass produced goods. the so-called «aging» of material is a result of deterioration in the properties of polymers due to chemical and physical changes caused by the effect of light, heat and humidity. many laboratories are conducting research to prevent these processes.
Task 1
1. Both the metals and the polymers can be alloyed.
2. It is possible to develop polymeric substances with the scheduled properties.
3. The so-called "aging" of the polymers is due to chemical and physical changes caused by the effect of light, heat and humidity.
Task 2
1. Polymers are characterized by their viscosity colour and softening points.
2. The properties of the polymers depend on their super-molecular structure.
3. The main concern of researchers and engineers is to improve the quality of mass produced goods.
Task 3
1. Polymers are widely used in industry.
2. Light, heat and humidity affect the polymers.
3. The main concern of the researchers and engineers is to improve the quality of polymers.