| The random copolymerized acrylic resin perform excellent, with less rigidity group, and poor heat resistance.So it can not be directly used as a pressure-sensitive adhesive. Micromolecule with reactive groups (e.g. epoxy) can be introduced as plasticizers. Also, polyurethane with dimer diol monomer has a flexible hexatomic ring and two large side chain of C9. These groups provid large steric hindrance, more free volume in the molecule, to make the PDMU a good low temperature performance. While it’s adhesion propertie is insufficient,so it is better to add terpene resin as a tackifier. For both systems, compatibility often suffer the combined effects of many conditions. In this paper, compatibility would be explored by experimental, theoretical, simulation method. Combining research system, structure of polymer can be designed through molecular dynamics simulations in advance, to find an appropriate compatibilization methods.1. The general modeling process steps of molecular dynamics simulation and the common problems had be explored and try to give solutions;Parameter settings, the external conditions, length of chain segment, functional groups and other factors impact on the process of modeling and molecular dynamics simulations results had be explored using the control variable method. Taking combined effects of various factors into account, the epoxy resin will be set as a structure of polymerization degree numbered0. As the temperature and pressure increases, the solubility parameter of acrylic resin/epoxy system getting closer. Also, solubility parameter δ gradually decreases with side chain functional groups is getting complicated.2. By molecular dynamics simulations, group contribution method, cosolvent and dilute solution viscosity method (DSV), compatibility of random copolymerized acrylic resin and DGEBA/DGEBF epoxy resin had be studied. The results show that increasing content of butyl acrylate and styrene, can lead to the increase of solubility parameter of the polymer, and the ompatibility of acrylic resin and bisphenol A epoxy resin is better than that of bisphenol F. Conclusion of molecular dynamics simulations method and experimental and theoretical calculation method is consistent.3. In the study of compatibility of polymer blends, group contribution method can be used to calculate the solubility of several candidate. It can be selected as the screening criteria. Because of the calculation error, it can be only used to select materials from the crowd. The co-solvent method commonly used in qualitative research, it can be used to exclude obviously incompatible system from several candidate materials; Computational molecular simulation method is very accurate, it can also predict solubility parameters changes in experimental conditions can not be achieved under extreme circumstances for difficult preparation system and the system which cosolvent method can not observe obvious phenomenon or system which difficult to prepared. While using theoretical calculations, experimental method, molecular dynamics simulations simultaneously, mutual correspondence and references can come more convincing results.4. Hereinbefore, the model is validated. Compatibility of the dimer diol-based polyurethane (PDMU) and monoterpene had be predicted. Ways to improve the compatibility of PDMU and monoterpenes are:increasing the soft segment content; improve consistency with paragraph ratio difference; controlled temperature between125-330K and so on. Designed polyurethane molecular structure, with soft segment content increasing compatibility of PDMU and monoterpene is beneficial. |
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