Zhang Danhua, academician Huang Wei of the Research Institute of flexible electronics of Northwest Polytechnic University (Center for advanced science of flexible electronics) of Shaanxi channel of people's daily client, and Professor Xie Linghai of the Research Institute of information materials and nanotechnology of Nanjing University of Posts and Telecommunications made major breakthroughs in the field of organic nanopolymers. The research results are "three-dimensional selection lattice and aggregation lattice based on the arrangement of central symmetrical molecules"（ "Stereoselective gridization and polygridization with centrosymetric molecular packing" was published online in nature communications on April 9.
Since Alan J. Heeger discovered conductive polymers in 1976 and won the Nobel Prize in chemistry in 2000, organic semiconductors and the flexible electronic technology based on them have become the most potential carriers for the future information industry and intelligent manufacturing. However, until now, flexible electronic technology, especially organic electronic technology, still faces great challenges, whether in organic display (OLED), organic laser (OL), organic photovoltaic (OPV), or in the field-effect transistor (OFET), sensing and execution, information storage and memory resistance calculation. Taking organic wide band gap semiconductor as an example, its comprehensive properties and material parameters are far lower than those of inorganic semiconductor represented by GaN / SiC. At present, only OLED has achieved large-scale commercialization, but also faces the fierce competition of quantum dots, perovskite, 2D nano and other emerging materials. In this context, it is of great scientific significance and technical value to return to the nature of organic semiconductors and to explore the underlying physical and chemical problems. In recent years, the team led by academician Huang Wei and Professor Xie Linghai proposed the concept of organic nanopolymers in view of molecular limitations, and created a new research direction of polymer like organic nanopolymers (Chin J polymer SCI 35, 87 – 97 (2017). Https://doi.org/10.1007/s10118-016-1856-7). Organic nano polymer is a kind of polymer which is made of organic nano monomer as repeat unit and covalently connected by nano. This kind of skeleton structure can take into account the chain property of carbon nano and the solvable processing advantage of polymer. Innovative structure development and synthesis strategy is the key to open up this direction. The synthesis of soluble, stereoselective and well-defined poly lattice nano polymers is not only the basis of photoelectric materials, but also particularly important for advanced models to reveal the relationship between structure and performance. In this study, the a2b2 type synthon designed by the team not only overcomes the cross-linking problem, but also can effectively control the structural regularity of the Nanopolymer. Starting from the "smart" theory proposed by the team, they used the π - π stacking attraction between electron donors and the charge repulsion force of protonated azafluorene to control the antiparallel and centrosymmetric molecular arrangement mode between super electrophilics, so as to overcome the interference of thermodynamic balance in the process of Friedel Crafts reaction and realize the inner reaction of lattice and poly lattice Racemic selectivity. There is a corresponding relationship between the angle deficient lattice formed by the dimer of A1B1 and the hand Sketcher created by Dutch master Moritz konelis Escher in 1948. Finally, they named this kind of organic nano polymer as drawing hands type Gridarene), this definition also represents the household meaning of nano connection, and it is expected that in the future, hand painting will become an effective chemical way of nano interconnection. It is worth mentioning that the hand drawn hand-held polymer lattice they synthesized shows the key characteristics of organic nano polymer and becomes an important milestone in this field. Polymer physics research shows that as the internal racemic choice of lattice based Nanopolymer (length of 20-30 nm), the main chain structure of this kind of ring chain alternating has the dependence of mark Houwink index of 1.651 and the hydrodynamic radius rh-m1.13, which proves that the hand drawn lattice has a rigid rod-shaped skeleton and the expected characteristics of Nanopolymer. In addition, the molecular dynamics simulation shows that the main chain of the internal racemic polymer lattice still has a highly anisotropic rod-shaped skeleton even in the collapse state, and shows a stronger anti collapse ability than the main chain of the external racemic polymer lattice. The breakthrough of stereoselective organic nanopolymers coincides with the 100th anniversary of the concept of polymer science proposed by Hermann Staudinger, the Nobel Prize winner in chemistry. We believe that the direction of organic nanopolymers created by them will open a new chapter in polymer science. According to academician Huang Wei, organic nano polymers will provide new solutions for plastic electronics, and their work in the future will potentially affect the new generation of organic broadband gap semiconductor materials, electric pump lasers, flexible electronic devices, printing and display technology, information storage and neural morphology computing, organic THz technology and other related scientific and technological frontier fields. The research work was supported by the general program of NSFC (21774061), the major research program integration program of NSFC (91833306), the innovation talent team project of "six talent peaks" of Jiangsu Province (xcl-cxtd-009), and Professor Lu Dan of Jilin University.