Primerjava časovno odvisnega modula relaksacije različnih materialov z uporabo preproste natezne naprave

Mohorko, Nik (author), Slemenik Perše, Lidija (mentor)

V nasprotju s kovinami so mehanske lastnosti polimerov izrazito časovno odvisne. V zaključni nalogi smo obravnavali spreminjanje modula relaksacije polimerov PTFE, PC, PVC, PP, ABS in PA6 s časom pri konstantni deformaciji. V ta namen smo zasnovali preprost natezni stroj s pnevmatskim vpetjem in računalniškim vmesnikom. Pokazali smo, da je spreminjanje modulov relaksacije sledilo predvidenemu obnašanju. Do največjega padca modula relaksacije med časoma t = 1 s in t = 1001 s je prišlo pri polimeru PTFE (39,9 %), do najmanjšega padca pa pri polimeru PC (10,5 %).

• Language: Slovenian
• Keywords: časovna odvisnost, polimeri, viskoelastičnost, modul relaksacije, natezni stroji
• Work type: Final paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [N. Mohorko]
• Year: 2019
• Number of pages: XIII, [24] f.
• PID: 20.500.12556/RUL-110154
• UDC: 539.3:678:620.172(043.2)
• COBISS.SI-ID: 16939547
• Publication date in RUL: 12.09.2019

Secondary language

• Language: English
• Title: Comparison of time dependent relaxation modulus of different polymeric materials using a simple tensile testing device

Abstract

In contrast to metals the mechanical properties of polymers are distinctively time-dependent. In this thesis we studied the relation of relaxation modulus of polymers PTFE, PC, PVC, PP, ABS and PA6 with time when subjected to a constant deformation. For this purpose, we developed a tensile testing device with pneumatic grips and a computer interface. We have concluded that the relaxation modulus-time relation followed the predicted behaviour. The greatest difference between modulus values in t = 1 s and t = 1001 s was observed with PTFE (39,9 %), while the smallest was observed with PC (10,5 %).

• Keywords: time-dependence, polymers, viscoelasticity, relaxation modulus, tensile testing devices