Regulation Of The Assembly Behavior Of Conjugated Molecules

Organic conjugated molecules are a class of molecular materials feathered with excellent photoelectric properties and delocalized electrons.Compared with inorganic molecules,organic conjugated molecules have many merits of molecular designability,low cost of raw materials and solution processability,which result in enormous attentions in many fields such as organic photoelectric materials,solar cells and biochemical sensors.For the past few years,researchers have been committed to developing novel organic conjugated molecules or regulating the assembly of existing organic conjugated molecules so as to adjust the properties for different goal.In this paper,we investigated molecular aggregation behavior by means of molecular design and regulating aggregation.On the one hand,the conjugated monomer based on RAFT polymerization was designed,and the assembly behavior of conjugated skeleton was regulated by covalently bridging the side chain of conjugated monomers to synthesize new two-dimensional material.On the other hand,PIC grafted with oligo(ethylene glycol)side chains,which exhibit a dendritic structure,is composed of a β-helical architecture stabilized by a peptidic hydrogen-bond network along the backbone.By dispersing water-soluble side chain conjugated oligomers with PIC,the assembly behavior of water-soluble conjugated oligo-electrolyte in water system is regulated,thus providing theoretical guidance for regulating the assembly behavior of conjugated molecules through non-covalent interaction.1.A polymer model based on Reversible Addition Fragmentation Chain Transfer(RAFT)polymerization method was established to fix substitution of side chains.The new type of organic conjugated molecules was prepared by regulating the assembly behavior of conjugated molecules through covalent bond.Reversible Addition Fragmentation Chain Transfer(RAFT)polymerization could provide abundant templates.Herein we utilize RAFT polymerization method to fix the substituted side chains,therefore controlling the orientation and planarity of the polymer skeleton.Novel organic conjugated polymers with different conformations and aggregation behaviors was designed and synthesized.In this paper,we prepared a variety of organic conjugated molecules with side chains polymerized by RAFT polymerization.Careful characterization illustrate that the organic conjugated molecules exhibit two-dimensional structure and strong intermolecular interactions(it is difficult to disperse the material with conventional solvents).In addition,the polymers showed good thermal stability.Side chain mono-blocked materials exhibit full wavelength absorption as graphene,while di-blocked molecules exhibit an obvious absorption peak,indicating that this method can result in a relatively obvious effect on regulating the aggregation behavior of conjugated skeletons,thus influencing the photoelectric properties of organic conjugated molecules.2.Non-covalent interaction was used to regulate the assembly behavior of PTTP to adjust electro-optical properties by simply mixing PIC and PTTP aqueous solutions.In order to control the organic conjugated oligo-electrolyte(PTTP)assembly behavior in the water system,we introduce a kind of hydrogel(PIC)including hydrophobic spiral structure and hydrophilic oligomeric ethylene glycol side chain.Due to the interaction between PTTP and PIC,the size of PTTP aggregates in water shrike,resulting in different photoelectric properties of PTTP.The fluorescence intensity of PTTP is greatly enhanced,and fluorescence quantity yield and fluorescence lifetime of PTTP are improved.Moreover,the generation capacity of ROS of PTTP is also increased.We verified the antibacterial effect of the composite by using plate counting method.Further studies showed that PIC,acting as a regulator,make PTTP efficiently embedded into the bacterial membrane to achieve stronger antibacterial effect.