مطالعه اثر وزن مولکولی پلی دی ال-لاکتیک اسید بر پارامترهای حافظه شکلی به کمک شبیهسازی دینامیک مولکولی
الموضوعات :
1 - دانشجوی مهندسی و علم مواد، دانشگاه خواجه نصیرالدین طوسی، تهران، ایران.
2 - دانشیار، دانشکده مهندسی و علم مواد، دانشگاه خواجه نصیرالدین طوسی، تهران، ایران.
الکلمات المفتاحية: وزن مولکولی, شبیهسازی دینامیک مولکولی, پلیلاکتیک اسید, خاصیت حافظه شکلی, دمای انتقال شیشهای,
ملخص المقالة :
پلیمرهای حافظه دار زیرمجموعهای از مواد هوشمند هستند که میتوانند شکل اولیهشان را بعد از تغییر شکل موقت بازیابی نمایند. این دسته از پلیمرها دارای کاربردهای فراوانی بوده و در سال های اخیر نظر بسیاری از صنایع (بهخصوص پزشکی) را به خود جلب کردهاند. هدف اصلی این مطالعه، بررسی تأثیر وزن مولکولی بر پارامترهای مختلف حافظه شکلی پلیمر میباشد. علاوه بر این، مکانیزم های حاکم بر رفتار حافظهداری پلیمرها مورد مطالعه قرار میگیرد. محاسبهی دمای انتقال شیشه ای و تأثیر این پارامتر بر رفتار حافظه شکلی پلیمر از دیگر اهداف این پژوهش می باشند. در این مطالعه، همه مدلها با نرمافزار متریالز استودیو ساخته شده و تمامی شبیهسازیها با استفاده از نرمافزار لمپس انجام شده است. طبق نتایج حاصل، دمای انتقال شیشهای پلیمر با افزایش درجه پلیمریزاسیون افزایش مییابد. ادامهی مطالعات در راستای دستیابی به ریزساختاری بهینه نشان داد که با افزایش وزن مولکولی از g/mol 36000 به g/mol108000، پارامتر تثبیت شکل از 90% به 94% افزایش مییابد. برخلاف تثبیت شکل، پارامتر بازیابی شکل روندی نزولی را با افزایش وزن مولکولی دنبال میکند. این روند کاهشی، ناشی از افزایش نسبت فاز ثابت به فاز بازگشتپذیر با افزایش وزن مولکولی پلیمر است.
[1] H. Meng & G. Li, "A review of stimuli-responsive shape memory polymer composites", Polymer, vol. 54, no. 9, pp. 2199-2221, 2013.
[2] W. Nie, C. Peng, X. Zhou, L. Chen, W. Wang, Y. Zhang, ... & C. He, "Three-dimensional porous scaffold by self-assembly of reduced graphene oxide and nano-hydroxyapatite composites for bone tissue engineering", Carbon, vol. 116, pp. 325-337, 2017.
[3] M. Amini & S. Wu, "Designing a polymer blend nanocomposite with triple shape memory effects", Composites Communications, vol. 23, pp. 100564, 2021.
[4] A. P. Gupta & V. Kumar, "New emerging trends in synthetic biodegradable polymers–Polylactide: A critique", European Polymer Journal, vol. 43, no. 10, pp. 4053-4074. 2007.
[5] Y. Saito, T. Tanaka, A. Andoh, H. Minematsu, K. Hata, T. Tsujikawa, ... & Y. Fujiyama, "Novel biodegradable stents for benign esophageal strictures following endoscopic submucosal dissection", Digestive Diseases and Sciences, vol. 53, no. 2, pp. 330-333, 2008.
[6] M. Amini, S. Kalantari & A. Khavandi, "Analysis of tensile failure mode and the mechanism dominated over polymer composite degradation", Journal of Science and Technology of Composites, vol. 6, no. 4, pp. 601-608, 2020.
[7] M. Amini & A. Khavandi, "Evaluation of the water absorption content effect on the dielectric properties and tensile strength of polymer composites", Journal of Science and Technology of Composites, vol. 6, no. 2, pp. 300-309, 2019.
[8] M. Amini & A. Khavandi, "Evaluation of the electrical properties and mechanical behavior of insulator’s composite core in harsh environments", Materials Research Express, vol. 5, no. 11, pp. 115306, 2018.
[9] S. H. Söntjens, T. A. Engels, T. H. Smit & L. E. Govaert, "Time-dependent failure of amorphous poly-d, l-lactide: Influence of molecular weight", Journal of the Mechanical Behavior of Biomedical Materials, vol. 13, pp. 69-77, 2012.
[10] X. L. Lu, W. Cai, Z. Gao & W. J. Tang, "Shape memory effects of poly (L-lactide) and its copolymer with poly (ε-caprolactone)", Polymer Bulletin, vol. 58, no. 2, pp. 381-391, 2007.
[11] Y. Liu, K. Gall, M. L. Dunn, A. R. Greenberg & J. Diani, "Thermomechanics of shape memory polymers: uniaxial experiments and constitutive modeling", International Journal of Plasticity, vol. 22, no. 2, pp. 279-313, 2006.
[12] T. D. Nguyen, H. J. Qi, F. Castro & K. N. Long, "A thermoviscoelastic model for amorphous shape memory polymers: incorporating structural and stress relaxation", Journal of the Mechanics and Physics of Solids, vol. 56, no. 9, pp. 2792-2814, 2008.
[13] Y. H. Wang, W. H. Wang, Z. Zhang, L. Xu & P. Li, "Study of the glass transition temperature and the mechanical properties of PET/modified silica nanocomposite by molecular dynamics simulation", European Polymer Journal, vol. 75, pp. 36-45, 2016.
[14] J. Diani & K. Gall, "Molecular dynamics simulations of the shape-memory behaviour of polyisoprene", Smart Materials and Structures, vol. 16, no. 5, pp. 1575, 2007.
[15] E. Ghobadi, M. Heuchel, K. Kratz & A. Lendlein, "Influence of the addition of water to amorphous switching domains on the simulated shape-memory properties of poly (L-lactide)", Polymer, vol. 54, no. 16, pp. 4204-4211, 2013.
[16] J. Moon, J. Choi & M. Cho, "Programmed shape-dependence of shape memory effect of oriented polystyrene: A molecular dynamics study", Polymer, vol. 102, pp. 1-9, 2016.
[17] S. Shi, Q. Liu, T. Xu & M. Oeser, "Study on the effect of transition temperature on shape memory behavior in polyurethane based on molecular dynamics simulation", Materials Research Express, vol. 6, no. 11, pp. 115323, 2019.
[18] A. Ben Abdallah, F. Gamaoun, A. Kallel & A. Tcharkhtchi, "Molecular weight influence on shape memory effect of shape memory polymer blend (poly (caprolactone)/ styrene-butadiene-styrene)", Journal of Applied Polymer Science, vol. 138, no. 5, pp. 49761, 2021.
[19] D. T. Semiromi & A. R. Azimian, "Molecular dynamics simulation of nonodroplets with the modified Lennard-Jones potential function", Heat and mass transfer, vol. 47, no. 5, pp. 579-588, 2011.
[20] D. Toghraie Semiromi & A. R. Azimian, "Nanoscale Poiseuille flow and effects of modified Lennard–Jones potential function", Heat and mass transfer, vol. 46, no. 7, pp. 791-801, 2010.
[21] D. Toghraie Semironi & A. R. Azimian, "Molecular dynamics simulation of liquid–vapor phase equilibrium by using the modified Lennard-Jones potential function", Heat and mass transfer, vol. 46, no. 3, pp. 287-294, 2010.
[22] M. Tohidi & D. Toghraie, "The effect of geometrical parameters, roughness and the number of nanoparticles on the self-diffusion coefficient in Couette flow in a nanochannel by using of molecular dynamics simulation", Physica B: Condensed Matter, vol. 518, pp. 20-32, 2017.
[23] P. Alipour, D. Toghraie, A. Karimipour & M. Hajian, "Modeling different structures in perturbed Poiseuille flow in a nanochannel by using of molecular dynamics simulation: Study the equilibrium", Physica A: Statistical Mechanics and its Applications, vol. 515, pp. 13-30, 2019.
[24] M. Tahmasebipour, R. Ahmadi M. Modarres, "Analysis of thermo-mechanical behavior of gold nanowire by using molecular dynamics method", in Persian, New Process in Material Engineering, vol. 13, no. 1, pp. 91-101, 2019.
[25] S. Plimpton, "Fast parallel algorithms for short-range molecular dynamics", Journal of Computational Physics, vol. 117, no. 1, pp. 1-19, 1995.
[26] Biovia DS. Materials Studio. R2 (Dassault Systèmes BIOVIA, San Diego); 2017.
[27] M. Amini, K. Hasheminejad & A. Montazeri, "Experimentally guided MD simulation to enhance the shape memory behavior of polymer-based nanocomposites: Towards elaborating the underlying mechanism", Composites Part A: Applied Science and Manufacturing, vol. 138, pp. 106055, 2020.
[28] S. Farah, D. G. Anderson & R. Langer, "Physical and mechanical properties of PLA, and
their functions in widespread applications–A comprehensive review", Advanced drug delivery reviews, vol. 107, pp. 367–92, 2016.
[29] H. Lian, W. Chang, Q. Liang, C. Hu, R. Wang, L. Zu & Y. Liu, "A shape memory polyurethane based ionic polymer–carbon nanotube composite", RSC advances, vol. 7, no. 73, pp. 46221-46228, 2017.
[30] C. Likitaporn, P. Mora, S. Tiptipakorn & S. Rimdusit, "Recovery stress enhancement in shape memory composites from silicon carbide whisker–filled benzoxazine-epoxy polymer alloy", Journal of Intelligent Material Systems and Structures, vol. 29, no. 3, pp. 388-396, 2018.
[31] N. Mirtschin & T. Pretsch, "Programming of one-and two-step stress recovery in a poly (ester urethane)", Polymers, vol. 9, no. 3, pp. 98, 2017.
[32] D. Hossain, M. A. Tschopp, D. K. Ward, J. L. Bouvard, P. Wang & M. F. Horstemeyer, "Molecular dynamics simulations of deformation mechanisms of amorphous polyethylene", Polymer, vol. 51, no. 25, pp. 6071-6083, 2010.
[33] S. Farah, D. G. Anderson & R. Langer, "Physical and mechanical properties of PLA, and their functions in widespread applications—A comprehensive review", Advanced drug delivery reviews, vol. 107, pp. 367-392, 2016.
[34] K. Hasheminejad & A. Montazeri, "Enhanced interfacial characteristics in PLA/graphene composites through numerically-designed interface treatment", Applied Surface Science, vol. 502, pp. 144150, 2020.
[35] M. Amini & A. Khavandi, "Synergistic effects of mechanical and environmental loading in stress corrosion cracking of glass/polymer composites", Journal of Composite Materials, vol. 53, no. 24, pp. 3433-3444, 2019.
[36] M. Amini & A. Khavandi, "Degradation of polymer-based composites in corrosive media: experimental attempts towards underlying mechanisms", Mechanics of Time-Dependent Materials, vol. 23, no. 2, pp. 153-172, 2019.
[37] R. H. Gee, N. Lacevic & L. E. Fried, "Atomistic simulations of spinodal phase separation preceding polymer crystallization", Nature Materials, vol. 5, no. 1, pp. 39-43, 2006.
[38] T. G. Fox Jr & P. J. Flory, "Second‐order transition temperatures and related properties of polystyrene. I. Influence of molecular weight", Journal of Applied Physics, vol. 21, no. 6, pp. 581-591, 1950.
[39] X. J. Zhang, Q. S. Yang, X. Liu, J. J. Shang & J. S. Leng, "Atomistic investigation of the shape-memory effect of amorphous poly (L-lactide) with different molecular weights", Smart Materials and Structures, vol. 29, no. 1, pp. 015040, 2019.
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