Strukturmodifizierung von Polyethylen durch plasmagepfropfte Acrylsäuregruppen

Abstract

Die Plasmatechnologic criiffnet ncue effiientc Miiglichkeiten fur eine gczieltc Struktur-und EigenschaftsmodiCizierung von Kunststoffen. In der vorliegenden Arbeit werden Untersuchungcn zur Anwendung der Plasmapolymerisation fur die Modifi~ierung von Polyethylen vorgestellt. Bei der Plasmapolymerisatictn wird organischer Dampf mit Hilk dcs Plasmas aktiviert. Die dabei erzeugten Radikale und Ioncn wcrden auf dcr Obcrfliiche des PE-Pulvers, das dem Plasma ausgesetzt is:, absorbiert und gehen eine feste Bindung cin. Dadurch entstehcn funkiionelle Gruppcn auf der Oberflache des PE-Pulvers. Am Bcispicl der Plasmapolymerisation mit Acryls2ure werden dic erziclten Ergebnisse der Strukturmodifizicrung von LDPE-Pulvcr vorgestellt.The plasma-technology offcrs new chances to modification of structure and properties from plastics.The topic of this work is the application oi plasma-polymerization to polyethylene. Plasmapolymerization means the activation of an organic vapour by plasma. A PE-powder absorbs the in that way generated radicals and ions. As a result Functional groups arc produced of the polyethylene-powder-suriace. The el'f'ects o f pJasma polymerization of acrylic acid on structur o C a LDPE-powder arc discussed.

Plasma treatment of polymer powders – from laboratory research to industrial application

“…X‐ray photoelectron spectroscopy (XPS) is widely used to analyze the powder's atomic surface composition and enables the identification of introduced functional groups . Fourier‐transform infrared spectroscopy (FTIR) and attenuated total reflectance infrared spectroscopy (ATR‐IR) are used to probe samples up to a depth of about 4–5 μm . Time of flight secondary ion mass spectroscopy (TOF‐SIMS) is utilized to evaluate the uniformity of plasma‐deposited polymer coatings by detecting sputtered ions and fragments.…”

“…Differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) are applied to study the thermal properties of the plasma‐treated polymer powders. Rheology provides information about the polymer viscosity, crosslinking, melting index, and the behavior under dynamic load.…”

“…The charge‐to‐mass blow‐off method is used to measure the powder charging. Adhesive tests (e.g., shear or tensile) are applied to test the strength of composites.…”

“…Plasma‐modified PE powder is often used as raw material for the production of parts using rotational molding technology . There are numerous studies dealing with improved adhesive bonding for powder coating applications on metal surfaces . Parts sintering enables direct painting and adhesive bonding without any additional surface pretreatment .…”

“…The plasma excitation is typically established by RF power coupling mechanisms, including inductive coupling with external copper coils, capacitive coupling with external half‐shell copper electrodes, inner center electrode, hexagonal barrel, or two adjustable outer copper electrodes . Other systems combined RF coupling with MW, pure MW coupling by means of a surface guide in a quartz tube, LF 40 KHz coupling, or LF combined with MW as implemented in the commercial “Nano” type plasma equipment of Diener Electronics GmbH…”