2025

• Li, Tao; Liu, Longhui; Zhang, Yuhua; Cheng, Dongyang; Guan, Yijia; Ravindranathan, Rini Padinjakkara. (2025) Polymer concentration and solvent quality-driven effects on chain structure and β conformation in poly(9,9-dioctylfluorene) solutions. Polymer
  Academic article
• Ravindranathan, Rini Padinjakkara; Olsmats, Eleonora; Ceccato, Bruno Telli; Knaapila, Matti Pekka; Fossum, Jon Otto; Knudsen, Kenneth Dahl. (2025) Pickering emulsions stabilized with β-lactoglobulin nanoparticles studied by small angle X-ray scattering: stability, aging and temperature effects. Soft Matter
  Academic article

2024

• Li, Tao; Zhang, Yuhua; Guan, Yijia; He, Qilong; Cheng, Dongyang; Almásy, László. (2024) The development of poly(9,9-dioctylfluorene) from solutions to solution processed films in terms of β-conformation: Perspective of molecular weight and solvent quality. Polymer
  Academic article
• Demchenko, Hanna; Fynbo, Cecilie; Huss-Hansen, Mathias K.; Kjelstrup-Hansen, Jakob; Knaapila, Matti Pekka. (2024) Naphthyl end-capped bithiophene film on plant-based polyamide-4,10. Thin Solid Films
  Academic article
• Yadav, Suraj; Pranav, Manasi; Gangadharappa, Chandrasekhar; Huss-Hansen, Mathias; Schwartzkopf, Matthias; Kjelstrup-Hansen, Jakob. (2024) Rational Third Component Choices Drive Enhanced Morphology and Efficiency in Ternary Blend Organic Solar Cells. ACS Energy Letters
  Academic article
• Sexton, Alexander Harold; Suhonen, Heikki; Huss-Hansen, Mathias K.; Demchenko, Hanna; Kjelstrup-Hansen, Jakob; Schwartzkopf, Matthias. (2024) Multi-scale correlation of impact-induced defects in carbon fiber composites using X-ray scattering and machine learning. Scientific Reports
  Academic article

2023

• Fynbo, Cecilie; Huss-Hansen, Mathias K.; Bikondoa, Oier; Gangadharappa, Chandrasekhar; Filho, Demetrio Antonio da Silva; Patil, Satish. (2023) Structural Study of Diketopyrrolopyrrole Derivative Thin Films: Influence of Deposition Method, Substrate Surface, and Aging. Langmuir
  Academic article
• Sexton, Alexander Harold; Kanters, Marc; Demchenko, Hanna; Pacáková, Barbara; Fossum, Jon Otto; Balzano, Luigi. (2023) Classifying Tensile Loading History of Continuous Carbon Fiber Composites Using X-Ray Scattering and Machine Learning. Advanced Engineering Materials
  Academic article
• Maity, Nilabja; Sharma, Manoj Kumar; Ghosh, Samrat; Huss-Hansen, Mathias K.; Roy, Ahin; Narayanan, Ravishankar. (2023) Supramolecular Self-Assembly of Diketopyrrolopyrrole with Unprecedented Photoconductivity. ACS Applied Electronic Materials
  Academic article
• Giordano, Nico; Guha, Suchismita; Stewart, Beverly; Kjelstrup-Hansen, Jakob; Knaapila, Matti Pekka. (2023) Second Order Phase Transition and Stabilizing CH···H and CH···S Interactions in Naphthyl End-Capped Bithiophene at 3.5 GPa. Journal of Physical Chemistry C
  Academic article

2022

• Costa, Telma; Knaapila, Matti Pekka; Stewart, Beverly; Ramos, M. Luísa; Justino, Licinia. L. G.; Valente, Artur J. M.. (2022) Nanostructuring with Surfactants: The Self-Assembly of a New Poly(thiophene-phenylene) Conjugated Polymer Bearing Azacrown Ether Pendant Groups. Langmuir
  Academic article
• Obdrup, Aksel S.; Wieland, D.C. Florian; Huss-Hansen, Mathias K.; Arras, Matthias M.L.; Knaapila, Matti Pekka. (2022) Classifying condition of ultra-high-molecular-weight polyethylene ropes with wide-angle X-ray scattering. Polymer testing
  Academic article
• Huss-Hansen, Mathias K.; Hedlund, Erik G.; Davydok, Anton; Hansteen, Marie; Overdijk, Jildert; Cremer, Gert de. (2022) Local structure mapping of gel-spun ultrahigh-molecular-weight polyethylene fibers. Polymer
  Academic article

2015

• Knaapila, Matti; Høyer, Henrik; Helgesen, Geir. (2015) Composite microdiscs with a magnetic belt: Preparation, chaining properties, and use as switchable catalyst carriers. ACS Applied Materials & Interfaces
  Academic article
• Sandsaunet, Marit Ulset; Knaapila, Matti; Tavares, Luciana; Kjelstrup-Hansen, Jacob; Helgesen, Geir. (2015) Parallel integration of aligned carbon strings in polymer composite: Dielectrophoretic preparation, finite element simulation, and electrical characterization. Polymer Composites
  Academic article

2014

• Guha, Suchismita; Knaapila, Matti; Moghe, Dhanashree; Konôpková, Zuzana; Torkkeli, Mika; Fritsch, Martin. (2014) Persistence of nematic liquid crystalline phase in a polyfluorene-based organic semiconductor: A high pressure study. Journal of Polymer Science Part B: Polymer Physics
  Academic article
• Knaapila, Matti; Fonseca, Sofia M.; Stewart, Beverly; Torkkeli, Mika; Perlich, Jan; Pradhan, Swapna. (2014) Nanostructuring of the conjugated polyelectrolyte poly[9,9-bis(4-sulfonylbutoxyphenyl)fluorene-2,7-diyl-2,2′-bithiophene] in liquid crystalline C12E4 in bulk water and aligned thin films. Soft Matter
  Academic article
• Knaapila, Matti; Costa, Telma; Garamus, Vasil M.; Kraft, Mario; Drechsler, Markus; Scherf, Ullrich. (2014) Conjugated polyelectrolyte (CPE) Poly{3-[6-(N -methylimidazolium)hexyl]-2, 5-thiophene} complexed with DNA: Relation between colloidal level solution structure and chromic effects. Macromolecules
  Academic article
• Knaapila, Matti; Høyer, Henrik; Helgesen, Geir. (2014) Dielectrophoresis in particle confinement: Aligned carbon particles in polymer matrix below percolation threshold. The European Physical Journal Special Topics (EPJ - Special Topics (EPJ ST))
  Academic literature review
• Knaapila, Matti; Høyer, Henrik; Kjelstrup-Hansen, Jacob; Helgesen, Geir. (2014) Transparency enhancement for photoinitiated polymerization (UV curing) through magnetic field alignment in a piezoresistive metal/polymer composite. ACS Applied Materials & Interfaces
  Academic article

2013

• Knaapila, Matti; Konopkova, Z; Torkkeli, M.; Haase, D.; Liermann, H-P; Guha, S. (2013) Structural study of helical polyfluorene under high quasihydrostatic pressure. Physical Review E. Statistical, Nonlinear, and Soft Matter Physics
  Academic article
• Knaapila, Matti; Monkman, Andrew P.. (2013) Methods for Controlling Structure and Photophysical Properties in Polyfluorene Solutions and Gels. Advanced Materials
  Academic literature review
• Knaapila, Matti; Torkkeli, Mika; Galbrecht, Frank; Scherf, Ullrich. (2013) Crystalline and Noncrystalline Forms of Poly(9,9-diheptylfluorene). Macromolecules
  Academic article
• Costa, Telma; Garner, Logan E.; Knaapila, Matti; Thomas, Alexander W.; Rogers, Sarah E.; Bazan, Guillermo C.. (2013) Aggregation Properties of p-Phenylene Vinylene Based Conjugated Oligoelectrolytes with Surfactants. Langmuir
  Academic article
• Knaapila, Matti; Torkkeli, Mika; Konôpková, Zuzana; Haase, Dörthe; Liermann, Hanns-Peter; Scherf, Ullrich. (2013) Measuring structural inhomogeneity of conjugated polymer at high pressures up to 30 GPa. Macromolecules
  Academic article

2012

• Høyer, Henrik; Knaapila, Matti; Kjelstrup-Hansen, Jacob; Liu, Xuhai; Helgesen, Geir. (2012) Individual strings of conducting carbon cones and discs in a polymer matrix: Electric field-induced alignment and their use as a strain sensor. Journal of Polymer Science Part B: Polymer Physics
  Academic article
• Burrows, Hugh D.; Knaapila, Matti; Fonseca, Sofia M.; Costa, Telma. (2012) Aggregation properties of conjugated polyelectrolytes.
  Academic chapter/article/Conference paper
• Johnsen, Gorm Krogh; Knaapila, Matti; Martinsen, Ørjan Grøttem; Helgesen, Geir. (2012) Conductivity enhancement of silver filled polymer composites through electric field alignment. Composites Science And Technology
  Academic article
• Høyer, Henrik; Knaapila, Matti; Kjelstrup-Hansen, Jacob; Helgesen, Geir. (2012) Microelectromechanical strain and pressure sensors based on electric field aligned carbon cone and carbon black particles in a silicone elastomer matrix. Journal of Applied Physics
  Academic article
• Helgesen, Geir; Knaapila, Matti; Skjeltorp, Arne Torbjørn; Høyer, Henrik; Cernak, J. (2012) Field induced microparticle structure formation in fluids. Revista Cubana de Física
  Academic article
• Evans, Rachel C.; Knaapila, Matti; Willis-Fox, Niamh; Kraft, Mario; Terry, Ann; Burrows, Hugh D.. (2012) Cationic Polythiophene-Surfactant Self-Assembly Complexes: Phase Transitions, Optical Response, and Sensing. Langmuir
  Academic article

2011

• Wang, Ellen; Ikonen, Teemu P.; Knaapila, Matti; Svergun, Dmitri; Logan, DT; Wachenfeld, Claes von. (2011) Small-angle X-ray Scattering Study of a Rex Family Repressor: Conformational Response to NADH and NAD(+) Binding in Solution. Journal of Molecular Biology (JMB)
  Academic article
• Guha, Suchi; Chandrasekhar, Meera; Scherf, Ulli; Knaapila, Matti. (2011) Tuning structural and optical properties of blue-emitting polymeric semiconductors. Physica status solidi (b)
  Academic article
• Høyer, Henrik; Knaapila, Matti; Kjelstrup-Hansen, Jacob; Liu, Xuhai; Helgesen, Geir. (2011) A strain sensor based on an aligned carbon particle string in a UV-cured polymer matrix. Applied Physics Letters
  Academic article
• Knaapila, Matti; Bright, Daniel W.; Nehls, Benjamin S.; Garamus, Vasil M.; Almásy, László; Schweins, Ralf. (2011) Development of Intermolecular Structure and Beta-phase of Random Poly[9,9-bis(2-ethylhexyl)fluorene]-co-(9,9-dioctylfluorene) in Methylcyclohexane. Macromolecules
  Academic article
• Knaapila, Matti; Evans, Rachel C.; Gutacker, Andrea; Garamus, Vasil M.; Székely, Noémi K.; Scherf, Ulrich. (2011) Conjugated polyelectrolyte (CPE) poly[3-[6-(N-methylimidazolium)hexyl]-2,5-thiophene] complexed with aqueous sodium dodecylsulfate amphiphile: synthesis, solution structure and "surfactochromic" properties. Soft Matter
  Academic article
• Justino, Licínia L.G.; Ramos, M. Luísa; Knaapila, Matti; Marques, Ana T.; Kudla, Christof J.; Scherf, Ulrich. (2011) Gel Formation and Interpolymer Alkyl Chain Interactions with Poly(9,9-dioctylfluorene-2,7-diyl) (PFO) in Toluene Solution: Results from NMR, SANS, DFT, and Semiempirical Calculations and Their Implications for PFO beta-Phase Formation. Macromolecules
  Academic article
• Knaapila, Matti; Bright, Daniel W.; Stepanyan, Roman; Torkkeli, Mika; Almásy, László; Schweins, Ralf. (2011) Network structure of polyfluorene sheets as a function of alkyl side chain length. Physical Review E. Statistical, Nonlinear, and Soft Matter Physics
  Academic article
• Knaapila, M.; Høyer, Henrik; Svåsand, Eldrid; Buchanan, Mark; Skjeltorp, Arne Torbjørn; Helgesen, Geir. (2011) Aligned Carbon Cones in Free-Standing UV-Curable Polymer Composite. Journal of Polymer Science Part B: Polymer Physics
  Academic article
• Knaapila, Matti; Svåsand, Eldrid; Pinheiro, Jean Patrick; Martinsen, Ørjan Grøttem; Buchanan, Mark; Skjeltorp, Arne Torbjørn. (2011) Conductivity Enhancement in Carbon Nanocone Adhesive by Electric Field Induced Formation of Aligned Assemblies. ACS Applied Materials & Interfaces
  Academic article
• Knaapila, Matti; Pinheiro, Jean Patrick; Buchanan, Mark; Skjeltorp, Arne Torbjørn; Helgesen, Geir. (2011) Directed assembly of carbon nanocones into wires with an epoxy coating in thin films by a combination of electric field alignment and subsequent pyrolysis. Carbon
  Academic article

2010

• Knaapila, Matti; Evans, Rachel C.; Garamus, Vasil M.; Aláasy, Laszló; Székely, Noémi K.; Gutacker, Andrea. (2010) Structure and "Surfactochromic" Properties of Conjugated Polyelectrolyte (CPE): Surfactant Complexes between a Cationic Polythiophene and SDS in Water. Langmuir
  Academic article
• Knaapila, Matti; Evans, Rachel C.; Gutacker, Andrea; Garamus, Vasil M.; Torkkeli, Mika; Adamczyk, Sylwia. (2010) Solvent Dependent Assembly of a Polyfluorene-Polythiophene "Rod-Rod" Block Copolyelectrolyte: Influence on Photophysical Properties. Langmuir
  Academic article
• Knaapila, Matti; Stepanyan, Roman; Haase, Dörthe; Carlson, Stephanie; Torkkeli, Mika; Cerenius, Yngve. (2010) Evidence for structural transition in hairy-rod poly[9,9-bis(2-ethylhexyl)fluorene] under high pressure conditions. Physical Review E. Statistical, Nonlinear, and Soft Matter Physics
  Academic article
• Gutacker, Andrea; Adamczyk, Sylwia; Helfer, Anke; Garner, Logan E.; Evans, Rachel C.; Fonseca, Sofia M.. (2010) All-conjugated polyelectrolyte block copolymers. Journal of Materials Chemistry
  Academic article
• Knaapila, Matti; Vaughan, Helen L.; Hase, Thomas P.A.; Evans, Rachel C.; Stepanyan, Roman; Torkkeli, Mika. (2010) Concentration Effect on the Oriented Microstructure in Tensile Drawn Polyfluorene-Polyethylene Blend. Macromolecules
  Academic article
• Gutacker, Andrea; Koenen, Nils; Scherf, Ulrich; Adamczyk, Sylwia; Pina, João; Fonseca, Sofia M.. (2010) Cationic fluorene-thiophene diblock copolymers: Aggregation behaviour in methanol/water and its relation to thin film structures. Polymer
  Academic article

2009

• Burrows, Hugh D.; Tapia, Maria J.; Fonseca, Sofia M.; Valente, Artur J.M.; Lobo, Victor M.M.; Justino, Licínia L.G.. (2009) Aqueous solution behavior of anionic fluorene-co-thiophene-based conjugated polyelectrolytes. ACS Applied Materials & Interfaces
  Academic literature review