Functional Core-Shell Micro- and Nanoparticles for Technical Applications Dr. Achim Weber Workshop: Anti-corrosion methods and condition monitoring for the oil and gas industry, IPT, São Paulo, Brazil, 22 nd March 2011
Overview Functional surfaces due to filled particles Corrosion inhibitors, nanocapsules Galvanic coating Plasma treatment of surfaces Technology overview Different geometries and coatings Anti corrosion coating 3D Laser printing Click chemistry Adjustable glass transition temperature, biocompatibility 2
Functional surfaces with liquid filled capsules Modificação das propriedades superficiais dos materiais através da integração de cápsulas em uma matrix metálica Innovation in surface modification Multidisciplinary development Combination between electrochemical methods and organic capsules C. B. Santos, M. Metzner, C. Mayer 2011 3
Functional surfaces with liquid filled capsules A functionalization of a metallic surface is achieved by the integration of nanocapsules into the matrix of a metallic coating. The capsules are meant to be electrodeposited together with the metal, forming a functional composite coating. Matriz metálica + cápsulas preenchidas com líquido = formação da camada metal/cápsules. Falha na camada leva a liberação do líquido (lubrificante, inibidor de corrosão,etc.) que fornece protreção local. Conventional AFM (left) and AFM phase image (right) of nanocapsules in a functionalized metallic coating. The black dots represent the soft mechanic response of the polymer capsules in the metallic coating layer. C. B. Santos, M. Metzner, C. Mayer 2011 4
Functional surfaces with liquid filled capsules Active agents (filling) Examples of active agents Corrosion inhibitors Lubricant Drugs Pigments Combination Exemplo de agentes ativos Inibidores de corrosão Lubrificantes Medicamentos Pigmentos e combinações de diferentes agentes ativos C. B. Santos, M. Metzner, C. Mayer 2011 5
Functional surfaces with liquid filled capsules Punctual mechanic load on the surface destroys some of the capsules, leading to a limited local release of the liquid content and initiating its desired function which may consist in a temporary anti-corrosive protection or in local lubrication of the surface. Desgaste da superfície metálica Efeito lubrificante do óleo contido nas cápsules, quando metal é desgastado. C. B. Santos, M. Metzner, C. Mayer 2011 SEM Micrograph from wear track after wear test with linear displacement against ceramic ball 6
Functional surfaces with liquid filled capsules: Electrodeposition Example: Metallic matrix (Zn, Ni, Cu) Capsules suspension (from 20 to 60 ml L -1 ) Deposition temp. (max. 50 C) a b Exemplos: Matriz metálica (Zn, Ni, CU) Suspensão com cápsules no eletólito (de 20 a 60 ml*l -1 ) Temperatura de deposição (max. 50 C) Valor de ph do eletrólito (entre 2 e 11) ph (from 2 to 11) SEM Microscopy (cross section) of the metallic matrix a) with and b) without capsules C. B. Santos, M. Metzner, C. Mayer 2011 7
Functional surfaces with liquid filled capsules: Wear tests Matrix Matrix + Capsule Efeito lubrificante: a redução do coeficiente de atrito indica melhora na lubrificação do material devido a presença de cápsules preenchidas com óleo. Nr. Sliding Wear tests on samples without and with capsules. The friction coefficient (µ) decreases with the addition of capsules in the coating. The capsules showed a lubricant effect in the metallic matrix. C. B. Santos, M. Metzner, C. Mayer 2011 8
Overview Functional surfaces due to filled particles Corrosion inhibitors, nanocapsules Galvanic coating Plasma treatment of surfaces Technology overview Different geometries and coatings Anti corrosion coating 3D Laser printing Click chemistry Adjustable glass transition temperature, biocompatibility 9
Low pressure plasma: Principle Gas inlet Electrode Vacuumchamber Electrode rf match Pump 10 z.b. 13,56 MHz
Plasma reactors: Examples area 660 cm 2 variable electrode distance heatable electrode area 1165 cm 2 plasma treatment of big samples (up to DIN A3) e.g. textiles Projektpartner Pink Plasma finish 11
Up and down scaling 12
Plasma for internal coating Hose Hose Bottles - barrier - residual draining 13
Easy-to-clean and anti-swelling coatings: Parylen layers coated Prevention of swelling Solvent resistence without coating 14
Plasma for protective coatings: Corrosion, fouling, icing Hexamethyldisiloxane (HMDSO) C 6 H 18 Si 2 O plasma polymerization hydrophilic (glass-like, protective SiO x coating) hydrophobic (preservation of the methylene groups) Trifluormethane CHF 3 Hexaflouropropylene C 3 F 6 or c-c 4 F 8 hydrophilic + oleophobic (application: e.g. antiicing surfaces on foils for aircraft and wind turbines) 15
Metalized polyester with and without plasma coating Corrosion Tests (a) (b) Optical microscope images of metalized (aluminum coated) polyester nonwoven after corrosion test (water condensation test 98 C 2h). (a) Without coating, corrosion takes place. (b) With plasma coating no corrosion can be recognized. 16
Overview Functional surfaces due to filled particles Corrosion inhibitors, nanocapsules Galvanic coating Plasma treatment of surfaces Technology overview Different geometries and coatings Anti corrosion coating 3D Laser printing Click chemistry Adjustable glass transition temperature, biocompatibility 17
3D Printing with electrophotography Printing unit Fusing unit Layer-by-layer assembly 18
Toner components Polymer particle Ø 1-30 µm zeon.co.jp Coating (Silica nanoparticles) 10-100 nm Additives (e.g. dye pigments) 19
Toner manufacturing Bulk polymer Air jet milling Extrusion and grinding konicaminolta.com irregular particles low resolution (< 300 dpi) 20
Chemical particle synthesis emt-india.net Clean up Heterogeneous polymerization Air drying spherical particles high resolution ( 600 dpi) 21
Particle fusion (Kumar et al., University of Florida) Thermal curing leads to deformation 22
Chemical fusion stability via covalent bonding ( click-chemistry ) requires mild conditions to protect functional surfaces 23
Chemical fusion stability via covalent bonding ( click-chemistry ) requires mild conditions to protect functional surfaces 24
Softening temperatures Methyl methacrylate T g (PMMA) = 379 K + Methyl acrylate T g (PMA) = 290 K Agglomeration at thermal initiation (AIBN, 60 C, 24 h) 25
Photopolymerization UV-reactors (4 units) Volume: 50 ml Polymer content: 5 g Temperature: 278 K Polymerization time: 24 h UV-lamp Volume: 1000 ml Polymer content: 100 g 26
Protective colloids Silica HDK N20 3 µm PVA (13% PVAc) PVP K30 6 µm 27
Protective colloids 28
Polymer functionalization 29
Outlook Building up tubes Model system for the electrophotographic rapid manufacturing process: Branched tube with bulk and surface made from different materials (bulk, interface, and support material) Fixation of un-combinable materials 30
Conclusion Liquid filled capsules for an anti-corrosion coating Plasma treatment for adjustable surface modifications: Protective coatings Different geometries for plasma coating available 3D electro photography: Conceivable via functionalized toner particles Particle manufacturing: Chemical synthesis favorable for high resolution printing & successful suspension polymerization via UV-initiation Particle modifications: Simple hydrolysis under basic conditions 31
Your partner from Fraunhofer IGB Dr. Achim Weber Group manager Particle-based Systems and Formulations Telefon +49 711 970-4022 achim.weber@igb.fraunhofer.de 32