From Chemistry Towards Technology Step-By-Step From Chemistry Towards Technology Step-By-Step От химии к технологии шаг за шагом 2782-1900 88838 10.52957/2782-1900-2024-5-3-23-36 Научные статьи Scientific articles Научные статьи Vliyanie katalizatora trimerizacii izocianata na himicheskij sostav i prochnostnye harakteristiki poliuretan-poliizocianuratnyh penoplastov Влияние катализатора тримеризации изоцианата на химический состав и прочностные характеристики полиуретан-полиизоциануратных пенопластов https://orcid.org/0000-0001-7738-7600 Власов Руслан Романович Vlasov Ruslan Romanovich vlasovruslan.hs@yandex.ru Зайцев Сергей Дмитриевич Zaycev Sergei Dmitrievich szay@inbox.ru

доктор химических наук;

doctor of chemical sciences;

 Нижегородский государственный университет им. Н.И. Лобачевского Нижний Новгород Россия Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod Russian Federation Нижегородский государственный университет им. Н.И. Лобачевского the Leading and National Research Nizhigorodsky State University named after N.I. Lobachevsky 24 09 2024 24 09 2024 5 3 23 36 29 05 2024 11 06 2024 https://chemintech.ru/en/nauka/article/88838/view

Полиуретан-полиизоциануратные (ПИР) пенопласты сегодня широко используются в качестве конструкционных и теплоизоляционных материалов. Катализаторы тримеризации изоцианата, используемые при синтезе данных пен, обладают довольно низкой селективностью по отношению к процессу образования изоцианурата. Как следствие, в рамках процесса синтеза ПИР пен протекает существенное количество не только целевых (первичных), но и побочных (вторичных) химических процессов. При помощи разработанных на основе метода внутреннего стандарта методик оценена зависимость расхода изоцианатных групп на образование основных первичных и вторичных продуктов от изоцианатного индекса композиции. Выявлено, что с повышением изоцианатного индекса конверсия изоцианата в изоцианурат существенно снижается. Исследовано влияние типа используемого катализатора тримеризации на химический состав и прочностные характеристики ПИР пенопластов. Показано, что катализаторы на основе органических солей щелочных металлов являются более селективными по отношению к процессу тримеризации изоцианата, чем третичные амины и производные четвертичных аммониевых оснований.

Полиуретан-полиизоциануратные (ПИР) пенопласты сегодня широко используются в качестве конструкционных и теплоизоляционных материалов. Катализаторы тримеризации изоцианата, используемые при синтезе данных пен, обладают довольно низкой селективностью по отношению к процессу образования изоцианурата. Как следствие, в рамках процесса синтеза ПИР пен протекает существенное количество не только целевых (первичных), но и побочных (вторичных) химических процессов. При помощи разработанных на основе метода внутреннего стандарта методик оценена зависимость расхода изоцианатных групп на образование основных первичных и вторичных продуктов от изоцианатного индекса композиции. Выявлено, что с повышением изоцианатного индекса конверсия изоцианата в изоцианурат существенно снижается. Исследовано влияние типа используемого катализатора тримеризации на химический состав и прочностные характеристики ПИР пенопластов. Показано, что катализаторы на основе органических солей щелочных металлов являются более селективными по отношению к процессу тримеризации изоцианата, чем третичные амины и производные четвертичных аммониевых оснований.

 полиуретан-полиизоциануратные пенопласты тримеризация изоцианата вторичные химические реакции конверсия изоцианата в изоцианурат остаточный изоцианат аллофанат карбодиимид прочность на сжатие

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