A dielectric ink thermal processing method has been developed to bond bicomponent poly(ethylene)/poly(propylene) (bico-PE/PP) fibers that are commonly used to make nonwoven fabrics for a variety of applications including medical, hygiene, and filtration needs. Dielectric inks applied to the fibers offer a number of potential advantages over conventional calendar bonding including more efficient energy conversion, faster heating rates, heating directed to desired bond sites, facile patterning, the ability to function on materials with substantial amounts of loft, and avoidance of fiber damage induced by calendar roller contact. Poly(ethylene) and poly(propylene) do not efficiently convert microwave energy to heat on their own; therefore, propylene carbonate (PC) and glycerine carbonate (GC) were selected as ink candidates due to their large dipole moments and dielectric constants. The temperature-dependent dielectric constant and dielectric loss values of both carbonates were measured as well as their thermal responses to microwave energy at 2.45 GHz. The dispersion of each carbonate on bico-PE/PP fibers, including the application to nonwoven fabrics, was characterized by optical microscopy. The thermal response for ink loading as a function of microwave radiation exposure time was investigated. Tensile test results showed that the bonding strength of dielectric ink bonded samples was comparable with the bonding obtained using conventional calendar bonding. The results presented herein demonstrate that dielectric inks provide fast heating rates, excellent fiber bonding, and the ability for facile nonwoven patterning.
|Number of pages||8|
|Journal||Colloids and Surfaces A: Physicochemical and Engineering Aspects|
|Publication status||Published - 5 Dec 2019|
- Dielectric ink
- Fiber bonding