Aliphatic Multi-generational, The Synthesis And Characterization Of Hyperbranched Polyurethane And The Structure And Performance Study

Hyperbranched polymer(HBP)is a kind of macromoleculewhich has highly branch and three-dimensional structural. It first reported by the researches of Dopont Company at the end of1980s and became the hot research spots in the polymer material fields because of it unique physical and chemical properties such as low viscosity, high rheologibility, good solubility, non chain entanglement, and large amount of terminal groups, which are different from the liner polymer. In two decades, the research area of hyperbranched polymer has developed from synthesis and the research of the chemical and physical properties to the molecular theory research, varic functionalizations and also the preliminarily researches of the application. Hyperbranched polymer has a broad prospect of application in the fields of drug-delivery.gene engineering. non-linear optics. nano-maierial. self-asssembly supermacromoleule.ener.gy transfer and acceptor. cataly sensor,rheloyical additive,and so on.Hvperbranched polyurethane (HPU) material has fixed much attention from the polymer materials scientists due to having both the excellent properties of polyurethane and the the unique structural characteristics of hyperbranched polymer. There have been many reports about the synthesis of HPU, but the comprehensive studies of the different generation products of the HPU have hardly been reported. The study in the different generation HPU is an innovative research work, it is useful for people to recognize the structure and properties of HPU. It also has the important academic value and the potential value of the practical application.This study using the simple and convenient monomers successfully prepared the different generation HWPU and solvent-based HPU products via the couple monomer reaction method and the NCO measurement. And then a series of the characterizations and tests were carried out on the products, respectively to study the relationships between the structure and performance.The major work includes the following two aspects: 1. the synthesis research of the different generation HWPU and solvent-based HPUThis experiment using isophorone diisocyanate (IPDI), dimethylolpropionic acid (DMPA) and diethanolamine (DEOA) as the main reaction monomers, through the A2+B2B*method synthesized AB2-type intermediate, and then polymerized to obtain the hyperbranched structure. The whole reaction course was monitored by the NCO value measured by the dibutylamine method. And using dibutylamine (DBA) as the terminator, the reaction was terminated when the measured NCO value and the theoretical NCO value was matched. Finally, the different generation HWPU and solvent-based HPU products were synthesized.All the products characterized by the FT-1R and NMR spectroscopy. And the results showed the hyperbranched structure was created. In conclusion.the different generation HPU products synthesized successfully.2. the study in the strueture and properties of the different generation HWPU and solvent-based IHPUEach generation of HWPU and solvent-based HPU products were characterized and tested by FTIR. N M R. thermogravimetric analyzer (TG) and differential scanning calorimetry (DSC), then studied the relationship between the hyperbranched structure and the performance.Compared the different generation HWPU and solvent-based HPU products which have similar chemical composition.the increase of generation barely affected the thermal decomposition processes. While the gla transition temperature (Tg) results showed that the Tg of the hyperbranched structure were increased with the increase of generation.