热致非晶态形状记忆聚合物的热粘弹性参数及回复行为
|
摘要
分别采用非线性拟合应力松弛主曲线及单个常频率条件下变温动态力学分析(DMA)实验中储能模量与损耗角正切曲线的方式,获取热致非晶态形状记忆聚合物(SMP)多重松弛模型中的热粘弹性参数。结合广义有限变形粘弹性理论和KAHR33参数热变形模型在有限元软件平台研究了该SMP的自由回复与约束回复行为。仿真结果与实验数据相符较好,说明该建模方法的合理性及获取的热粘弹性参数的准确性。相比构建应力松弛和储能模量主曲线而言,单个DMA实验数据更易得到,因此对其拟合能大幅减少实验成本。
The thermoviscoelastic parameters of the multiple relaxation model for the thermally activated amorphous shape memory polymers( SMPs) were determined from the stress relaxation master curve and from the storage modulus and the loss angle of a single dynamic mechanical analysis( DMA) temperature sweep at constant frequency by the nonlinear regression method,respectively. The behaviors of the free recovery and the constrained recovery of the SMP were studied in Abaqus coupled with the generalized finite deformation viscoelastic theory and KAHR 33-parameter model of thermal expansion. For the simulation results fit well with the test data,it is proved that the modeling approach is reasonable and the thermoviscoelastic parameters obtained by the approaches are precise. Since it is complicated to construct the stress relaxation and the storage modulus master curves,the approach by which the thermoviscoelastic parameters are determined from a single DMA could significantly reduces expenses on experiment.
The thermoviscoelastic parameters of the multiple relaxation model for the thermally activated amorphous shape memory polymers( SMPs) were determined from the stress relaxation master curve and from the storage modulus and the loss angle of a single dynamic mechanical analysis( DMA) temperature sweep at constant frequency by the nonlinear regression method,respectively. The behaviors of the free recovery and the constrained recovery of the SMP were studied in Abaqus coupled with the generalized finite deformation viscoelastic theory and KAHR 33-parameter model of thermal expansion. For the simulation results fit well with the test data,it is proved that the modeling approach is reasonable and the thermoviscoelastic parameters obtained by the approaches are precise. Since it is complicated to construct the stress relaxation and the storage modulus master curves,the approach by which the thermoviscoelastic parameters are determined from a single DMA could significantly reduces expenses on experiment.
引文
[1]Leng J S,Lan X,Liu Y J,et al.Shape-memory polymers and their composites:stimulus methods and applications[J].Prog.Mater.Sci.,2011,56:1077-1135.
[2]Tobushi H,Hashimoto T,Hayashi S,et al.Thermomechanical constitutive modeling in shape memory polymer of polyurethane series[J].J.Intell.Mater.Syst.Struct.,1997,8:711-718.
[3]李郑发,王正道.热致形状记忆聚合物的热力学性能[J].高分子材料科学,2012,28(1):71-74.Li Z F,Wang Z D.Thermomechanical properties of shapememory polymer[J].Polymer Materials Science&Engineering,2012,28(1):71-74.
[4]Nguyen T D,Qi H J,Castro F,et al.A thermoviscoelastic model for amorphous shape memory polymers:Incorporating structural and stress relaxation[J].J.Mech.Phys.Solids,2008,56:2792-2814.
[5]Westbrook K K,Kao P H,Castro F,et al.A 3D finite deformation constitutive model for amorphous shape memory polymers:a multibranch modeling approach for nonequilibrium relaxation processes[J].Mech.Mater.,2011,43:853-869.
[6]Diani J,Gilormini P,Frédy C,et al.Predicting thermal shape memory of crosslinked polymer networks from linear viscoelasticity[J].Int.J.Solids Struct.,2012,49:793-799.
[7]Ge Q,Yu K,Ding Y F,et al.Prediction of temperature-dependent free recovery behaviors of amorphous shape memory polymers[J].Soft Matter,2012,8:11098-11105.
[8]Simo J C.On a fully three-dimensional finite strain viscoelastic damage model:formulation and computational aspects[J].Comput.Method Appl.M.,1987,60:153-173.
[9]Pulla S S,Souri M,Karaca H E,et al.Characterization and strainenergy-function-based modeling of the thermomechanical response of shape-memory polymers[J].J.Appl.Polym.Sci.,2015,132:41861.
[10]Kovacs A J,Aklonis J J,Hutchinson J M,et al.Isobaric volume and enthalpy recovery of glasses.II.A transparent multiparameter theory[J].J.Polym.Sci.:Polym.Phys.Ed.,1979,17:1062-1097.
[2]Tobushi H,Hashimoto T,Hayashi S,et al.Thermomechanical constitutive modeling in shape memory polymer of polyurethane series[J].J.Intell.Mater.Syst.Struct.,1997,8:711-718.
[3]李郑发,王正道.热致形状记忆聚合物的热力学性能[J].高分子材料科学,2012,28(1):71-74.Li Z F,Wang Z D.Thermomechanical properties of shapememory polymer[J].Polymer Materials Science&Engineering,2012,28(1):71-74.
[4]Nguyen T D,Qi H J,Castro F,et al.A thermoviscoelastic model for amorphous shape memory polymers:Incorporating structural and stress relaxation[J].J.Mech.Phys.Solids,2008,56:2792-2814.
[5]Westbrook K K,Kao P H,Castro F,et al.A 3D finite deformation constitutive model for amorphous shape memory polymers:a multibranch modeling approach for nonequilibrium relaxation processes[J].Mech.Mater.,2011,43:853-869.
[6]Diani J,Gilormini P,Frédy C,et al.Predicting thermal shape memory of crosslinked polymer networks from linear viscoelasticity[J].Int.J.Solids Struct.,2012,49:793-799.
[7]Ge Q,Yu K,Ding Y F,et al.Prediction of temperature-dependent free recovery behaviors of amorphous shape memory polymers[J].Soft Matter,2012,8:11098-11105.
[8]Simo J C.On a fully three-dimensional finite strain viscoelastic damage model:formulation and computational aspects[J].Comput.Method Appl.M.,1987,60:153-173.
[9]Pulla S S,Souri M,Karaca H E,et al.Characterization and strainenergy-function-based modeling of the thermomechanical response of shape-memory polymers[J].J.Appl.Polym.Sci.,2015,132:41861.
[10]Kovacs A J,Aklonis J J,Hutchinson J M,et al.Isobaric volume and enthalpy recovery of glasses.II.A transparent multiparameter theory[J].J.Polym.Sci.:Polym.Phys.Ed.,1979,17:1062-1097.