Graphene as reinforcing filler in polyvinyl acetate resin

Author(s):  
Hamid R. Taghiyari ◽  
Roya Majidi ◽  
Seyed Majid Mohseni Armaki ◽  
Mohammadreza Haghighatparast
2003 ◽  
Vol 778 ◽  
Author(s):  
Rajdip Bandyopadhyaya ◽  
Weizhi Rong ◽  
Yong J. Suh ◽  
Sheldon K. Friedlander

AbstractCarbon black in the form of nanoparticle chains is used as a reinforcing filler in elastomers. However, the dynamics of the filler particles under tension and their role in the improvement of the mechanical properties of rubber are not well understood. We have studied experimentally the dynamics of isolated nanoparticle chain aggregates (NCAs) of carbon made by laser ablation, and also that of carbon black embedded in a polymer film. In situ studies of stretching and contraction of such chains in the transmission electron microscope (TEM) were conducted under different maximum values of strain. Stretching causes initially folded NCA to reorganize into a straight, taut configuration. Further stretching leads to either plastic deformation and breakage (at 37.4% strain) or to a partial elastic behavior of the chain at small strains (e.g. 2.3% strain). For all cases the chains were very flexible under tension. Similar reorientation and stretching was observed for carbon black chains embedded in a polymer film. Such flexible and elastic nature of NCAs point towards a possible mechanism of reinforcement of rubber by carbon black fillers.


Author(s):  
С.П. Исаев ◽  
К.А. Шевчук

Современное развитие деревоперерабатывающей отрасли сопровождается существенным ростом объемов готовой продукции, производимой на основе клееной древесины. Качество выпускаемой клееной продукции во многом определяется свойствами применяемых клеев. Экспериментально исследовано влияние электромагнитного поля СВЧ-диапазона на структуру клеев, применяемых для склеивания древесины. Установлено, что СВЧ-обработка оказывает существенное влияние на микроструктуру поливинилацетатного клея Dorus 072. Структура клеевой пленки, обработанной СВЧ-излучением, имеет более высокую дисперсность, по сравнению с исходным полимером, которая выражается в среднем уменьшении глобул в 1,4 раза. Исследование фазового контраста пленки поливинилацетатного клея, обработанного СВЧ-излучением, позволило установить, что после обработки уменьшается фазовая неоднородность клеевой пленки и имеет место углубление дисперсности глобул полимера, приводящее к увеличению степени его упаковки с образованием однородной по структуре пленки. Экспериментальные исследования пленок карбамидоформальдегидного клея Dorus FU 406, подвергнутого СВЧ-обработке, показали, что структуры образцов пленок как обработанного, так и необработанного, клея не отличаются значительными изменениями. Исследование фазового сдвига по поверхности образца пленки карбамидоформальдегидного клея отражает распределение свойств материала и показывает, что СВЧ-обработка клея способствует образованию квазигомогенной структуры, формирование которой подтверждается уменьшением различий в границах фазовых переходов микроструктур отвержденного полимера. На основании проведенных экспериментов по исследованию структуры пленок клеев, применяемых для склеивания древесины, установлено, что в результате воздействия электромагнитного поля СВЧ-диапазона на клеевые растворы осуществляется нетепловая модификация, сопровождающаяся уменьшением размеров макромолекул полимера и формированием плотно упакованной структуры пленки. Полученные результаты позволяют сделать вывод о целесообразности дальнейших исследований по модификации клеев СВЧ-обработкой. Modern development of woodworking branches is accompanied by essential growth of volumes of the finished goods manufactured on the basis of glued wood. Quality of let out glued production in many respects is defined by properties of applied glues. Influence of an electromagnetic field of a microwave range on frame of the glues applied to coagglutination of wood is experimentally investigated. It is positioned that microwave processing makes essential impact on a microstructure of polyvinyl acetate glue Dorus 072. The frame of the adhesive film treated by microwave radiation, has higher dispersity in comparison with initial polymer which is expressed on the average reduction of globules in 1,4 times. Research of phase contrast of a film of the treated polyvinyl acetate glue by microwave radiation has allowed to position that after processing phase heterogeneity of an adhesive film decreases and the excavation of dispersity of globules of the polymer, leading to augmentation of degree of its packaging, forming an unimodal film on frame takes place. Experimental researches of films of amino-formaldehyde glue Dorus FU 406, subjected to microwave processing, have shown that Frames of samples of films both treated, and untreated glue do not differ significant changes. Research of phase alteration on a surface of the sample of a film of amino-formaldehyde glue reflects allocation of properties of a stuff and shows that glue microwave processing promotes formation of the quasi-homogeneous frame which formation proves to be true reduction of distinctions in borders of phase changes of microstructures hardning polymer. On the basis of the made experiments on research of frame of films of the glues applied to coagglutination of wood it is positioned that as a result of influence of an electromagnetic field of the microwave oven of a range on glutinous solutions not thermal modification accompanied by reduction of the dimensions of macromolecules of polymer and formation of densely packed frame of a film is carried out. The received results allow to draw a conclusion on expediency of the further researches on modification of glues by microwave processing.


Author(s):  
G. F. Zhelezina ◽  
V. G. Bova ◽  
S. I. Voinov ◽  
A. Ch. Kan

The paper considers possibilities of using a hybrid fabric made of high-modulus carbon yarn brand ZhGV and high-strength aramid yarns brand Rusar-NT for polymer composites reinforcement. The results of studies of the physical and mechanical characteristics of hybrid composite material and values of the implementation of the strength and elasticity carbon fibers and aramid module for composite material are presented. 


2020 ◽  
Vol 11 (6) ◽  
pp. 1390-1396
Author(s):  
G. F. Zhelezina ◽  
V. G. Bova ◽  
S. I. Voinov ◽  
A. Ch. Kan

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1128
Author(s):  
Sylwia Członka ◽  
Anna Strąkowska ◽  
Agnė Kairytė

In this study, coir fibers were successfully modified with henna (derived from the Lawsonia inermis plant) using a high-energy ball-milling process. In the next step, such developed filler was used as a reinforcing filler in the production of rigid polyurethane (PUR) foams. The impact of 1, 2, and 5 wt % of coir-fiber filler on structural and physico-mechanical properties was evaluated. Among all modified series of PUR composites, the greatest improvement in physico-mechanical performances was observed for PUR composites reinforced with 1 wt % of the coir-fiber filler. For example, on the addition of 1 wt % of coir-fiber filler, the compression strength was improved by 23%, while the flexural strength increased by 9%. Similar dependence was observed in the case of dynamic-mechanical properties—on the addition of 1 wt % of the filler, the value of glass transition temperature increased from 149 °C to 178 °C, while the value of storage modulus increased by ~80%. It was found that PUR composites reinforced with coir-fiber filler were characterized by better mechanical performances after the UV-aging.


Author(s):  
I. Mendolia ◽  
C. Zanca ◽  
F. Ganci ◽  
G. Conoscenti ◽  
F. Carfì Pavia ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document