Synthesis and characterisation of well-defined comb copolymers
5РП — Човешки потенциал в науката
- Период
- 2002-03-01 → 2003-02-28
- Финансиране от ЕС
- 57 736 €
- Участници
- 1
- Схема
- RGI
Линиите свързват координатора с партньорите.
Накратко на български
Гребеновидните кополимери се синтезират чрез комбиниране на два химични метода, за да се създадат структури с полистиролни разклонения върху полинорборененова основа. Това помага да се разбере как разтворителите, температурата и концентрацията влияят върху дължината и плътността на полимерните вериги.
Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.
Цел на проекта
In this work the potential of combining the capabilities of living anionic and ROMP methods will be further explored to prepare polymers with well-defined structures and unusual topologies. This approach will be used to prepare a range of comb copolymers that cannot be prepared by grafting onto or from homopolymer backbones. The method will allow rational design and synthesis of comb copolymers with control over the main chain and graft-chain molecular weights and also the graft density. The comb copolymers consist of a polynorbornene backbone carrying, one and two polystyrene grafts on each cyclopentane ring. The earlier result of the ROMP of macro monomers carrying two and one polystyrene graft on each cyclopentane ring using molybdenum t-butoxy initiator in benzene at room temperature revealed that the comb copolymer backbone chain grows up to a certain length beyond which the ROMP reaction becomes sterically hindered and eventually stops. The results also suggested that, in contrast to two polystyrene grafts on the norbornene unit, with one polystyrene graft on the norbornene unit comb copolymers with relatively long backbone and graft chains can be prepared probably as a consequence of lowered steric hindrance. The programme of work described here is directed at evaluating the effects of different solvent and hence different comb copolymer configurations, the temperature, the level of activity of the ROMP initiators and the concentration on the ROMP stage and particularly on the length of the backbone chains attainable in comb copolymers. The ROMP reactions will be carried out in benzene, dichloromethane (or chloroform) and THF at room temperature, 40°C and 60°C. The ROMP reaction will also be carried out at low, medium and high concentration to evaluate the effect of the concentration. Furthermore, the effect of ROMP initiators of different activity on the ROMP process will be studied by using 5 well-defined initiators.
Оригинален текст от CORDIS (на английски).
Участници
- UNIVERSITY OF DURHAM · DURHAMКоординаторОбединеното кралство
Връзки
Данни: CORDIS, © Европейски съюз