柔性二官能度化合物易与环磷腈形成环状结构,不能形成好的交联网络,使含醛基环磷腈(CP-3AP)与间苯二甲胺(MxDA)、己二胺(HDA)构筑的聚亚胺热可逆材料溶解到四氢呋喃中。增加CP-3AP中非交联侧基位阻,阻碍这种环化结构形成,实现了醛基环磷腈与不同氨基化合物均能构筑不溶的可逆交联网络,同时探讨了位阻对交联程度的影响。
Flexible bifunctional compounds are easy to form cyclic structures with cyclophosphazene,which prevents the formation of an effective crosslinked network.As a result,thermoreversible polyimine materials constructed from CP-3AP and m-xylylenediamine (MxDA),hexamethylenediamine (HDA) could dissolve in tetrahydrofuran (THF).The formation of the cyclic structures could be impeded by increasing the steric hindrance of non-crosslinked groups of CP-3AP,which enabled the aldehyde groups of cyclophosphazene to form insoluble reversible crosslinked networks with different amino compounds.Meanwhile,the effect of steric hindrance on crosslinking degree was explored.
[1] Wang S,Ma S,Li Q,et al.Robust,fire-safe,monomer-recovery,highly malleable thermosets from renewable bioresources[J].Macromolecules,2018,51:8001-8012.
[2] Jie Z,Zhuang M P,Shi H N,et al.Vitrimers:current research trends and their emerging applications[J].Materials Today,2021,51:586-625.
[3] Mo R,Jin H,Huang H,et al.Tunable,self-healing and corrosion inhibiting dynamic epoxy-polyimine network built by post-crosslinking[J].Journal of Materials Chemistry A,2019,7(7):3031-3038.
[4] Lei X,Jin Y,Sun H,et al.Rehealable imide-imine hybrid polymers with full recyclability[J].Journal of Materials Chemistry A,2017,5:21140-21145.
[5] Lei Z,Xie P,Rong M,et al.Catalyst-free dynamic exchange of aromatic Schiff base bonds and its application to self-healing and remolding of crosslinked polymers[J].Journal of Materials Chemistry,A.Materials for Energy and Sustainability,2015,3:19662-19668.
[6] Zhu J B,Watson E M,Tang J,et al.A synthetic polymer system with repeatable chemical recyclability[J].Science,2018,360(6387):398-403.
[7] Feng X,Fan J,Li A,et al.Multireusable thermoset with anomalous flame-triggered shape memory effect[J].ACS Applied Materials & Interfaces,2019,11:16075-16086.
[8] Feng X,Li G.Versatile phosphate diester-based flame retardant vitrimers via catalyst-free mixed transesterification[J].ACS Applied Materials & Interfaces,2020,12:57486-57496.
[9] Feng X,Li G.Catalyst-free β-hydroxy phosphate ester exchange for robust fire-proof vitrimers[J].Chemical Engineering Journal,2021,417:129132.
[10] Zheng N,Hou J,Xu Y,et al.Catalyst-free thermoset polyurethane with permanent shape reconfigurability and highly tunable triple-shape memory performance[J].ACS Macro Letters,2017,6:326-330.
[11] Loche M,Schmitt J,Decher G,et al.Detailed structure of molecularly thin polyelectrolyte multilayer films on solid substrates as revealed by neutron reflectometry[J].Macromolecules,1998,31(25):8893-8906.
[12] Allcock H R,Teeter Stein M.Clathration by tris(2,3-naphthalenedioxy)cyclotriphos-phazene:an X-ray crystal and molecular structure study[J].Journal of the American Chemical Society,1974,96(1):49-52.
[13] Allcock H R,Levin M L.Stereocontrolled polymerization within a tris(o-pheny1enedioxy)cyclotriphosphazene of acrylic monomers tunnel clathrate[J].Macromolecules,1985,18(6):1324-1330.
[14] Allcock H R,Silverberg E N,Dudley G K.Stereocontrolled polymerization within a cyclophosphazene clathrate tunnel system[J].Macromolecules,1994,27(4):1033-1038.
[15] Allcock H R,Ferrar W T,Levin M L.Polymerization in clathrate tunnel systems:stereocontrolled polymerization of unsaturated monomers in crystals of tris(o-phenylenedioxy)cyclotriphosphazene[J].Macromolecules,1982,15(3):697-703.
[16] 卢艳飞.环三磷腈的希夫碱基衍生化、结构和性质研究[D].大连:辽宁师范大学,2013.
[17] Zhang X,Eichen Y,Miao Z,et al.Novel phosphazene-based flame retardant polyimine vitrimers with monomer-recovery and high performances[J].Chemical Engineering Journal,2022,440:135806.
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