Magnetomechanical and Magnetothermal Coupling in Ferrohydrogels

  • E. Roeben
  • L. Roeder
  • R. Messing
  • N. Frickel
  • G. Marten
  • T. Gelbrich
  • A. M. Schmidt
Conference paper
Part of the Progress in Colloid and Polymer Science book series (PROGCOLLOID, volume 140)


By merging soft, hydrogel-based matrices with nanoscopic inorganic nanoparticles to organic-inorganic hybrid materials, novel properties can arise from the unique interplay of the components´ properties. The introduction of magnetic nanoparticles of different size and shape into hydrophilic polymer network architectures leads to nano- or macroscopic hybrid gel structures that respond to magnetic fields in a predetermined way. A variety of complex gel structures are designed that allow a mutual interaction of their mechanical and thermal properties. In this review, we highlight recent accomplishments and trends in the field of magnetically active hybrid hydrogels, and conclude with an outline on future prospects in the design and application of magnetic soft matter with particle-matrix interaction.


Particle-matrix interaction Magnetic soft matter Superparamagnetism Biomedical applications Magnetostriction Magnetoactive materials 



This work was supported by the Deutsche Forschungsgemeinschaft (DFG) within the priority programme SPP 1259 “Intelligent Hydrogels”, and partly by the Emmy Noether programme (SCHM1747-4).


  1. 1.
    De Las Heras Alarcon C, Pennadam S, Alexander C (2005) Stimuli responsive polymers for biomedical applications. Chem Soc Rev 34:276–285Google Scholar
  2. 2.
    Messing R, Schmidt AM (2011) Perspectives for the mechanical manipulation of hybrid hydrogels. Polym Chem 2:18–32Google Scholar
  3. 3.
    Karg M (2012) Multifunctional inorganic/organic hybrid microgels. Colloid Polym Sci 290:673–688Google Scholar
  4. 4.
    Dagallier C, Dietsch H, Schurtenberger P, Scheffold F (2010) Thermoresponsive hybrid microgel particles with intrinsic optical and magnetic anisotropy. Soft Matter 6:2174Google Scholar
  5. 5.
    Laurenti M, Guardia P, Contreras-Cáceres R, Pérez-Juste J, Fernandez-Barbero A, Lopez-Cabarcos E, Rubio-Retama J (2011) Synthesis of thermosensitive microgels with a tunable magnetic core. Langmuir 27:10484–10491Google Scholar
  6. 6.
    Schmidt AM (2007) Thermoresponsive magnetic colloids. Colloid Polym Sci 285:953–966Google Scholar
  7. 7.
    Craig D (1995) Magnetism – principles and applications. Wiley, ChichesterGoogle Scholar
  8. 8.
    Berkovsky BM, Bashtovoy V (1996) Magnetic fluids and applications handbook. Begell House, New YorkGoogle Scholar
  9. 9.
    Blums E, Cbers A, Mairov MM (1997) Magnetic fluids. Walter der Gruyter, BerlinGoogle Scholar
  10. 10.
    Brown W (1959) Relaxational behavior of fine magnetic particles. J Appl Phys 30:S130Google Scholar
  11. 11.
    Andrä W, Nowak H (1998) Magnetism in medicine. Wiley-VCH, BerlinGoogle Scholar
  12. 12.
    Reinicke S, Döhler S, Tea S, Krekhova M, Messing R, Schmidt AM, Schmalz H (2010) Magneto-responsive hydrogels based on maghemite/triblock terpolymer hybrid micelles. Soft Matter 6:2760–2773Google Scholar
  13. 13.
    Kaiser A, Winkler M, Krause S, Finkelmann H, Schmidt AM (2009) Magnetoactive liquid crystal elastomer nanocomposites. J Mater Chem 19:538–543Google Scholar
  14. 14.
    Kaiser A, Gelbrich T, Schmidt AM (2006) Thermosensitive magnetic fluids. J Phys Condens Matter 18:S2563–S2580Google Scholar
  15. 15.
    Schmidt A (2005) Induction heating of novel thermoresponsive ferrofluids. J Magn Magn Mater 289C:5–8Google Scholar
  16. 16.
    Schmidt AM (2005) The synthesis of magnetic core-shell nanoparticles by surface-initiated ring-opening polymerization of e-caprolactone. Macromol Rapid Comm 26:93–97Google Scholar
  17. 17.
    Feyen M, Heim E, Ludwig F, Schmidt A (2008) Magnetic nanorotors with tailored field-induced dynamics. Chem Mater 20:2942–2948Google Scholar
  18. 18.
    Sinnwell S, Ritter H (2006) Ring-opening homo- and copolymeriza tion of -methylene--caprolactone. Macromolecules 39:2804–2807Google Scholar
  19. 19.
    Winkler M, Kaiser A, Krause S, Finkelmann H, Schmidt AM (2010) Liquid crystal elastomers with magnetic actuation. Macromol Symp 291/2:186–192Google Scholar
  20. 20.
    Levine I, Zvi RB, Winkler M, Schmidt AM, Gottlieb M (2010) Magnetically induced heating in elastomeric nanocomposites – theory and experiment. Macromol Symp 291/2:278–286Google Scholar
  21. 21.
    Lu A, Li W, Kiefer A, Schmidt W, Bill E, Fink G, Schüth F (2004) Fabrication of magnetically separable mesostructured silica with an open pore system. J Am Chem Soc 126:8616–8617Google Scholar
  22. 22.
    Katz E, Willner I (2005) Switching of directions of bioelectrocatalytic currents and photocurrents at electrode surfaces by using hydrophobic magnetic nanoparticles. Angew Chem Int Ed 44:4791–4794Google Scholar
  23. 23.
    Lee Y, Lee J, Bae CJ, Park J, Noh H, Park J, Hyeon T (2005) Large scale synthesis of uniform and crystalline magnetite nanoparticles using reverse micelles as nanoreactors under reflux conditions. Adv Funct Mater 15:503–509Google Scholar
  24. 24.
    Franzreb M, Siemann-Herzberg M, Hobley TJ, Thomas ORT (2006) Protein purification using magnetic adsorbent particles. Appl Microbiol Biotechnol 70:505–516Google Scholar
  25. 25.
    Gu H, Xu K, Xu C, Xu B (2006) Biofunctional magnetic nanoparticles for protein separation and pathogen detection. Chem Commun. 941–949Google Scholar
  26. 26.
    Horák D, Babic M, Macková H, Benes MJ (2007) Preparation and properties of magnetic nano- and microsized particles for biological and environmental separations. J Separ Sci 30:1751–1772Google Scholar
  27. 27.
    Safarík I, Safaríková M (1999) Use of magnetic techniques for the isolation of cells. J Chromatogr B: Biomed Sci Appl 722:33–53Google Scholar
  28. 28.
    Safarik I, Safarikova M (2004) Magnetic techniques for the isolation and purification of proteins and peptides. Biomagn Res Technol 2:7Google Scholar
  29. 29.
    Pankhurst Q, Connolly J, Jones SK, Dobson J (2003) Applications of magnetic nanoparticles in biomedicine. J Phys D Appl Phys 36:R167–R181Google Scholar
  30. 30.
    Massart R, Cabuil V (1987) Effect of some parameters on the formation of magnetic nanoparticles. J Chim Phys 84:967–973Google Scholar
  31. 31.
    Marten GU, Gelbrich T, Schmidt AM (2010) Hybrid biofunctional nanostructures as stimuli-responsive catalytic systems. Beilstein J Org Chem 6:922–931Google Scholar
  32. 32.
    Guo J, Yang W, Wang C, He J, Chen J (2006) Poly (N-isopropylacrylamide) -coated luminescent//magnetic silica microspheres: preparation, characterization, and biomedical applications. Chem Mater 18:5554–5562Google Scholar
  33. 33.
    Müller-Schulte D, Schmitz-Rode T (2006) Thermosensitive magnetic polymer particles as contactless controllable drug carriers. J Magn Magn Mater 302:267–271Google Scholar
  34. 34.
    Schmidt AM, Messing R, Lu Y, Ballauff M. unpublished resultsGoogle Scholar
  35. 35.
    Kondo A, Fukuda H (1997) Preparation of thermo-sensitive magnetic hydrogel microspheres and application to enzyme immobilization. J Ferment Bioeng 84:337–341Google Scholar
  36. 36.
    Ding X, Sun Z, Zhang W (2000) Adsorption/desorption of protein on magnetic particles covered by thermosensitive polymers. J Appl Polym Sci 77:2915–2920Google Scholar
  37. 37.
    Elaissari A, Bourrel V (2001) Thermosensitive magnetic latex particles for controlling protein adsorption and desorption. J Magn Magn Mater 225:151–155Google Scholar
  38. 38.
    Frickel N, Messing R, Gelbrich T, Schmidt AM (2010) Functional silanes as surface modifying primers for the preparation of highly stable and well-defined magnetic polymer hybrids. Langmuir 26:2839–2846Google Scholar
  39. 39.
    Deng YH, Yang WL, Wang CC, Fu SK (2003) A novel approach for preparation of thermoresponsive polymer magnetic microspheres with core–shell structure. Adv Mater 15:1729–1732Google Scholar
  40. 40.
    Gürler C, Feyen M, Behrens S, Matoussevitch N, Schmidt AM (2008) One-step synthesis of functional Co nanoparticles for surface-initiated polymerization. Polymer 49:2211–2216Google Scholar
  41. 41.
    Kaiser A, Dutz S, Schmidt A.M (2009) Kinetic studies of surface-initiated atom transfer radical polymerization in the synthesis of magnetic fluids. J Polym Sci: Part A: Polymer Chemistry, 47: 7012–7020Google Scholar
  42. 42.
    Toy AA, Reinicke S, Mu AHE (2007) One-pot synthesis of polyglycidol-containing block copolymers with alkyllithium initiators using the phosphazene base t-BuP4. Macromolecules 40:5241–5244Google Scholar
  43. 43.
    Tanaka T (1978) Collapse of gels and the critical endpoint. Phys Rev Lett 40:820Google Scholar
  44. 44.
    Osada Y, Gong J-P (1998) Soft and wet materials: polymer gels. Adv Mater 10:827–837Google Scholar
  45. 45.
    Rao GVR, Krug ME, Balamurugan S, Xu H, Xu Q, López GP (2002) Synthesis and characterization of silica-poly (N-isopropylacrylamide) hybrid membranes: switchable molecular filters. Chem Mater 14:5075–5080Google Scholar
  46. 46.
    Garreau S, Leclerc M, Errien N, Louarn G (2003) Planar-to-nonplanar conformational transition in thermochromic polythiophenes: a spectroscopic study. Macromolecules 36:692–697Google Scholar
  47. 47.
    Otsuka K, Wayman CM (1998) Shape memory materials. Cambridge University Press, CambridgeGoogle Scholar
  48. 48.
    Lendlein A, Schmidt AM, Schroeter M, Langer R (2005) Shape-memory polymer networks from oligo(-caprolactone) dimethacrylates. J Polym Sci: Part A: Polymer Chemistry, 43:1369–1381Google Scholar
  49. 49.
    Kelch S, Steuer S, Schmidt AM, Lendlein A (2007) Shape-memory polymer networks from oligo[(epsilon-hydroxycaproate)-co-glycolate]dimethacrylates and butyl acrylate with adjustable hydrolytic degradation rate. Biomacromolecules 8:1018–1027Google Scholar
  50. 50.
    Zhou J, Schmidt AM, Ritter H (2010) Bicomponent transparent polyester networks with shape memory effect. Macromolecules 43:939–942Google Scholar
  51. 51.
    Keerl M, Smirnovas V, Winter R, Richtering W (2008) Interplay between hydrogen bonding and macromolecular architecture leading to unusual phase behavior in thermosensitive microgels. Angew Chem 120:344–347Google Scholar
  52. 52.
    Keerl M, Richtering W (2006) Synergistic depression of volume phase transition temperature in copolymer microgels. Colloid Polym Sci 285:471–474Google Scholar
  53. 53.
    Meid J, Dierkes F, Cui J, Messing R, Crosby AJ, Schmidt A, Richtering W (2012) Mechanical properties of temperature sensitive microgel/polyacrylamide composite hydrogels—from soft to hard fillers. Soft Matter 8:4254Google Scholar
  54. 54.
    Lutz J-F (2011) Thermo-switchable materials prepared using the OEGMA-platform. Adv Mater 23:2237–2243Google Scholar
  55. 55.
    Gelbrich T, Reinartz M, Schmidt AM (2010) Active ester functional single core magnetic nanostructures as a versatile immobilization matrix for effective bioseparation and catalysis. Biomacromolecules 11:635–642Google Scholar
  56. 56.
    Gelbrich T, Feyen M, Schmidt AM (2006) Magnetic thermoresponsive core-shell nanoparticles. Macromolecules 39:3469–3472Google Scholar
  57. 57.
    Gelbrich T, Feyen M, Schmidt AM (2006) Magnetic polymer brushes: towards tailor-made stabilization of magnetic fluids by surface-initiated polymerization. Z Phys Chem 220:41–49Google Scholar
  58. 58.
    Gelbrich T, Marten GU, Schmidt AM (2010) Reversible thermoflocculation of magnetic core–shell particles induced by remote magnetic heating. Polymer 51:2818–2824Google Scholar
  59. 59.
    Kaiser A, Schmidt AM (2008) Phase behavior of polystyrene-brush-coated nanoparticles in cyclohexane. J Phys Chem B 112:1894–1898Google Scholar
  60. 60.
    Messing R, Schmidt AM (2008) Heat Transfer from Nanoparticles to the Continuum Matrix. Surface and Interfacial Forces - From Fundamentals to Applications. Progr Colloid Polym Sci 134:134–140Google Scholar
  61. 61.
    Schexnailder P, Schmidt G (2008) Nanocomposite polymer hydrogels. Colloid Polym Sci 287:1–11Google Scholar
  62. 62.
    Lao LL, Ramanujan RV (2004) Magnetic and hydrogel composite materials for hyperthermia applications. J Mater Sci Mater Med 15:1061–1064Google Scholar
  63. 63.
    Ramanujan RV, Ang KL, Venkatraman S (2006) Magnet–PNIPA hydrogels for bioengineering applications. J Mater Sci 44:1381–1387Google Scholar
  64. 64.
    Pankhurst QA, Thanh NTK, Jones SK, Dobson J (2009) Progress in applications of magnetic nanoparticles in biomedicine. J Phys D Appl Phys 42:224001Google Scholar
  65. 65.
    Guowei D, Adriane K, Chen X, Jie C, Yinfeng L (2007) PVP magnetic nanospheres: biocompatibility, in vitro and in vivo bleomycin release. Int J Pharm 328:78–85Google Scholar
  66. 66.
    Liu T, Hu S, Liu T, Liu D, Chen S (2006) Magnetic-sensitive behavior of intelligent ferrogels for controlled release of drug. Langmuir 22:5974–5978Google Scholar
  67. 67.
    Elaissari A (2005) Magnetic colloids: preparation and biomedical applications. e-Polymers. 5:296–306Google Scholar
  68. 68.
    Chang Y, Su Z (2002) Preparation and characterization of thermosensitive magnetic particles. Mater Sci Eng, A 333:\break 155–159Google Scholar
  69. 69.
    Xiao L, Li J, Brougham DF, Fox EK, Feliu N, Bushmelev A, Schmidt A, Mertens N, Kiessling F, Valldor M, Fadeel B, Mathur S (2011) Water-soluble superparamagnetic magnetite nanoparticles with biocompatible coating for enhanced magnetic resonance imaging. ACS Nano 5:6315–6324Google Scholar
  70. 70.
    Schmidt AM, Gelbrich T, Marten G, Reinartz M, Schrader J unpublished resultsGoogle Scholar
  71. 71.
    Erlanger B, Kokowsky N, Cohen W (1961) The preparation and properties of two new chromogenic substrates of trypsin. Arch Biochem Biophys 95:271–278Google Scholar
  72. 72.
    Marten GU, Gelbrich T, Ritter H, Schmidt AM (2013) A magnetoresponsive drug delivery system via ß-cyclodextrin functionalized magnetic polymer brushes. IEEE Trans Magn 49:364–370Google Scholar
  73. 73.
    Van De Manakker F, Vermonden T, Van Nostrum CF, Hennink WE (2009) Cyclodextrin-based polymeric materials: synthesis, properties, and pharmaceutical/biomedical applications. Biomacromolecules 10:3157–3175Google Scholar
  74. 74.
    Loftsson T, Brewster ME (2011) Pharmaceutical applications of cyclodextrins: effects on drug permeation through biological membranes. J Pharm Pharmacol 63:1119–1135Google Scholar
  75. 75.
    Munteanu M, Choi S, Ritter H (2008) Cyclodextrin methacrylate via microwave-assisted click reaction. Macromolecules 41:9619–9623Google Scholar
  76. 76.
    Choi S, Munteanu M, Ritter H (2009) Monoacrylated cyclodextrin via “click” reaction and copolymerization with N-isopropylacrylamide: guest controlled solution properties. J Polym Res 16:389–394Google Scholar
  77. 77.
    Frelichowska J, Bolzinger M-A, Valour J-P, Mouaziz H, Pelletier J, Chevalier Y (2009) Pickering w/o emulsions: drug release and topical delivery. Int J Pharm 368:7–15Google Scholar
  78. 78.
    Kaiser A, Liu T, Richtering W, Schmidt AM (2009) Magnetic capsules and pickering emulsions stabilized by core-shell particles. Langmuir 25:7335–7341Google Scholar
  79. 79.
    Zrinyi M, Barsi L, Büki A (1997) Ferrogel: a new magneto-controlled elastic medium. Polym Gels Netw 5:415–427Google Scholar
  80. 80.
    Szabò D, Szeghy G, Zrínyi M (1998) Shape transition of magnetic field sensitive polymer gels. Macromolecules 31:6541–6548Google Scholar
  81. 81.
    Ramanujan RV, Lao LL (2006) The mechanical behavior of smart magnet – hydrogel composites. Smart Mater Struct 15:952–956Google Scholar
  82. 82.
    Qin J, Asempah I, Laurent S, Fornara A, Muller RN, Muhammed M (2009) Injectable superparamagnetic ferrogels for controlled release of hydrophobic drugs. Adv Mater 21:1354–1357Google Scholar
  83. 83.
    Raikher YL, Stolbov OV (2005) Deformation of an ellipsoidal ferrogel sample. J Appl Mech Tech Phys 46:434–443Google Scholar
  84. 84.
    Stepanov GV, Abramchuk SS, Grishin DA, Nikitin LV, Kramarenko EY, Khokhlov AR (2007) Effect of a homogeneous magnetic field on the viscoelastic behavior of magnetic elastomers. Polymer 48:488–495Google Scholar
  85. 85.
    Mauguin G (1988) Continuum mechanics of electromagnetic solids. North-Holland, AmsterdamGoogle Scholar
  86. 86.
    Borcea L, Bruno O (2001) On the magneto-elastic properties of elastomer–ferromagnet composites. J Mech Phys Solids 49:2877–2919Google Scholar
  87. 87.
    Bustamante R, Dorfmann A, Ogden RW (2006) A nonlinear magnetoelastic tube under extension and inflation in an axial magnetic field: numerical solution. J Eng Math 59:139–153Google Scholar
  88. 88.
    Diguet G, Beaugnon E, Cavaillé JY (2009) From dipolar interactions of a random distribution of ferromagnetic particles to magnetostriction. J Magn Magn Mater 321:396–401Google Scholar
  89. 89.
    Zrinyi M (2000) Intelligent polymer gels controlled by magnetic fields. Colloid Polym Sci 103:98–103Google Scholar
  90. 90.
    Ginder JM, Nichols ME, Elie LD, Tardiff JL (1999) Magnetorheological elastomers: properties and applications. Proc SPIE 3675:131Google Scholar
  91. 91.
    Farshad M, Benine A (2004) Magnetoactive elastomer composites. Polym Test 23:347–353Google Scholar
  92. 92.
    Park TG, Hoffmann AS (1993) Thermal cycling effects on the bioreactor performances of immobilized β-galactosidase in temperature-sensitive hydrogel beads. Enzyme Microb Technol 15:476–482Google Scholar
  93. 93.
    Kato N, Oishi A, Takahashi F (1998) Enzyme reaction controlled by magnetic heating due to the hysteresis loss of γ-Fe2O3 in thermosensitive polymer gels immobilized. Mater Sci Eng C: Biol 6:291–296Google Scholar
  94. 94.
    Schmidt AM (2006) Electromagnetic activation of shape memory polymer networks containing magnetic nanoparticles. Macromol Rapid Comm 27:1168–1172Google Scholar
  95. 95.
    Kato N, Yamanobe S, Takahashi F (1997) Property of magneto-driven poly(N-isopropylacrylamide) gel containing γ- in NaCl solution as a chemomechanical device. Mater Sci Eng C 5:141–147Google Scholar
  96. 96.
    Satarkar NS, Zhang W, Eitel RE, Hilt JZ (2009) Magnetic hydrogel nanocomposites as remote controlled microfluidic valves. Lab Chip 9:1773–1779Google Scholar
  97. 97.
    Barbucci R, Pasqui D, Giani G, De Cagna M, Fini M, Giardino R, Atrei A (2011) A novel strategy for engineering hydrogels with ferromagnetic nanoparticles as crosslinkers of the polymer chains. Potential applications as a targeted drug delivery system. Soft Matter 7:5558–5565Google Scholar
  98. 98.
    Pasqui D, Atrei A, Giani G, Cagna MD, Barbucci R (2011) Metal oxide nanoparticles as cross-linkers in polymeric hybrid hydrogels. Mater Lett 65:392–395Google Scholar
  99. 99.
    Messing R, Frickel N, Belkoura L, Strey R, Rahn H, Odenbach S, Schmidt AM (2011) Cobalt ferrite nanoparticles as multifunctional cross-linkers in PAAm ferrohydrogels. Macromolecules 44:2990–2999Google Scholar
  100. 100.
    Fuhrer R, Athanassiou EK, Luechinger NA, Stark WJ (2009) Crosslinking metal nanoparticles into the polymer backbone of hydrogels enables preparation of soft, magnetic field-driven actuators with muscle-like flexibility. Small 5:383–388Google Scholar
  101. 101.
    Frickel N, Messing R, Schmidt AM (2011) Magneto-mechanical coupling in -linked PAAm ferrohydrogels. J Mater Chem 21:8466Google Scholar
  102. 102.
    Galicia JA, Cousin F, Dubois E, Sandre O, Cabuil V, Perzynski R (2009) Static and dynamic structural probing of swollen polyacrylamide ferrogels. Soft Matter 5:2614–2624Google Scholar
  103. 103.
    Barrera C, Florián-Algarin V, Acevedo A, Rinaldi C (2010) Monitoring gelation using magnetic nanoparticles. Soft Matter 6:3662–3668Google Scholar
  104. 104.
    Janas V, Rodriguez F, Cohen C (1980) Aging and thermodynamics of polyacrylamide gels. Macromolecules 13:977–983Google Scholar
  105. 105.
    Nossal R (1985) Network formation in polyacrylamide gels. Macromolecules 18:49–54Google Scholar
  106. 106.
    Richards EG, Temple CJ (1971) Some Properties of Polyacrylamide Gels. Natl Phys Sci 230:92–96Google Scholar
  107. 107.
    Zhang J, Daubert C, Foegeding E (2005) Characterization of polyacrylamide gels as an elastic model for food gels. Rheol Acta 44:622–630Google Scholar
  108. 108.
    Foegeding EA, Gonzalez C, Hamann DD, Case S (1994) Polyacrylamide gels as elastic models for food gels. Food Hydrocolloid 8:125–134Google Scholar
  109. 109.
    Veverka M, Veverka P, Kaman O, Lančok A, Závěta K, Pollert E, Knížek K, Boháček J, Beneš M, Kašpar P, Duguet E, Vasseur S (2007) Magnetic heating by cobalt ferrite nanoparticles. Nanotechnology 18:345704Google Scholar
  110. 110.
    Ozaki M, Kratohvil S, Matijević E (1984) Formation of monodispersed spindle-type hematite particles. J Colloid Interface Sci 106:146–151Google Scholar
  111. 111.
    Roeder L, Bender P, Tschöpe A, Birringer R, Schmidt AM (2012) Shear modulus determination in model hydrogels by means of elongated magnetic nanoprobes. J Polym Sci Part B: Polym Phys 50:1772–1781Google Scholar
  112. 112.
    Flory PJ, Rehner J (1943) Statistical Mechanics of Cross-Linked Polymer Networks II. Swelling. J Chem Phys 11:521–526Google Scholar
  113. 113.
    Mark JE (1982) Experimental Determinations of Crosslink Densities. Rubber Chem Technol 55:762–769Google Scholar
  114. 114.
    Frenkel J (1938) Acta Phys USSR 9:235–250Google Scholar
  115. 115.
    Frenkel J (1940) A theory of Elasticity, Viscosity and Swelling in Polymeric Rubber-Like Substances. Rubber Chem Technol 13:264–274Google Scholar
  116. 116.
    Stoner EC, Wohlfarth EP (1948) A mechanism of magnetic hysteresis in heterogeneous alloys. Philos Transact R Soc A 240:599–642Google Scholar
  117. 117.
    Schulz L, Schirmacher W, Omran A, Shah VR, Böni P, Petry W, Müller-Buschbaum P (2010) Elastic torsion effects in magnetic nanoparticle diblock-copolymer structures. J Phys Condens Matter 22:346008Google Scholar
  118. 118.
    Bender P, Günther A, Tschöpe A, Birringer R (2013) Determination of the shear modulus of gelatine hydrogels by magnetization measurements using dispersed nickel nanorods as mechanical probes. J Magn Magn Mat 346:152–160Google Scholar
  119. 119.
    Coffey TW, Kalmykov YP, Waldron JT (2004) The Langevin equation. World Scientific Publishing, LondonGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2013

Authors and Affiliations

  • E. Roeben
    • 1
  • L. Roeder
    • 1
  • R. Messing
    • 1
  • N. Frickel
    • 1
  • G. Marten
    • 1
  • T. Gelbrich
    • 1
  • A. M. Schmidt
    • 1
  1. 1.Institut für Physikalische Chemie, Department ChemieUniversität zu KölnKölnGermany

Personalised recommendations