Polypropylene (PP)/poly(ethylene terephthalate) (PET) bicomponent (bico) fibres are successfully melt blown in the Reicofil® meltblown (MB) pilot line commissioned at the Textiles and Nonwovens Development Center (TANDEC), the University of Tennessee, Knoxville. The bico fibers possess a cross‐sectional side‐by‐side configuration. The originally expected greater fiber crimp due to density and fine structure gradients on the different sides of the bico fibers was not commonly observed in the normal MB webs. These fabrics were exposed to dry heat for a period of time. The properties before and after the heat treatment were determined and compared to investigate the effects of heat on their properties. It was found that the bico webs are thermal dimensionally stable and many of their properties were not significantly affected. A mechanism is suggested on the thermal dimensional stability of the PP/PET bico MB webs. © 2003 Society of Chemical Industry

ABSTRACT:Meltblowing is a most versatile and costeffective process commercially available worldwide to produce microfiber nonwovens directly from thermoplastic resins. The new bicomponent (bico) meltblown technology opens a great possibility to make even finer microfibers by subsequently fiber splitting. Water-dispersive Eastman AQ polymers were initially introduced to the meltblown process to make the mono-and bicomponent meltblown webs at Textiles and Nonwovens Development Center (TANDEC), University of Tennessee, Knoxville. The postwater treatment was performed on the fabrics, which resulted in the dispersive part (AQ polymer) being dispersed in water and only the other part remaining in the bico web. A process-structure-property study is provided toward the research reported in this article.

Poly(trimethylene terephthalate) (PTT)-based mono and bico meltblown webs have been produced by using a Reicofil® Bi-Component Meltblown Line at TANDEC, located at the University of Tennessee, Knoxville, TN. Thermal and flow properties of PTT were first examined by DSC (differential scanning calorimetry) and with a Melt Indexer for an effective experimental design through the Surface Response Methodology (SRM). The processability of meltblowing in a wide range of operating windows was extensively investigated. Melt temperature, melt throughput, air temperature, airflow rate, and DCD (distance of collector to die) were considered as primary process control variables. The produced webs were characterized for fiber diameter, bulk density, air permeability, hydrostatic head, tensile properties, and heat shrinkage. Non-round and curly or twisted fibers were observed in the bico PP/PTT webs by SEM (scanning electrical microscope). The PTT grade studied is quite suitable for the meltblown process. The PTT/PP-based bico webs showed enhanced barrier properties and heat resistance.

Corona discharge introduces polar groups into the polymeric surfaces and, as a consequence, improves the surface energy, wettability, and adhesion characteristics. The main chemical mechanism of corona treatment is oxidation. This article further discusses some special problems that are related to corona treatment of polyolefin films by reviewing the recent developments in this field, such as effect of corona treatment on adhesion, effect of resin additives on corona treatment, insufficient treatment and over‐treatment of corona discharge, aging, and re‐treatment. © 1999 John Wiley & Sons, Inc. Adv Polym Techn 18: 171–180, 1999

Side-by-side bicomponent meltblown fiber webs were developed on REICOFIL ® bicomponent (bico) meltblown line at The University of Tennessee's Textiles and Nonwovens Development Center (TANDEC), using polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyamide (PA), polytrimethylene terephthalate (PTT), and so forth. The posttreatment was performed by hydroentanglement to investigate the fiber-splitting behavior in this research. Microscopy analysis and SEM were applied to examine the web structure. The change in web property after posttreatment and the adhesion mechanism of the polymer interface were also addressed.

Cotton-based nonwovens have been developed at Textiles and Nonwovens Development Center (TANDEC), The University of Tennessee, with the cotton fibers on the surface or in the core layer laminated with meltblown (MB) and/or spunbonded (SB) webs. Both Cotton-Surfaced Nonwovens (CSN) and Cotton-Core Nonwovens (CCN) have excellent soft hand, breathability, absorbency, and tensile properties making them ideal for many medical applications such as isolation gowns, hospital drapes and gowns, shoe covers, head covers, underwear, pillowcases, diaper components (acquisition, core, back sheet), feminine hygiene pads, baby wipes, etc. In this paper, the processes to produce these cotton-surfaced nonwovens will be presented, including as-bonded, heat-stretched CSN fabrics, and foam-finished CSN nonwovens.

In this article a small amount (4%) of a series of polymer additives were blended with polypropylene (Exxon 3746G) and polyester (Eastman 14965) polymers and the mixtures were processed. The effect of these additives on the surface energy of the polymers was characterized by the contact angle measured on single fibers and by surface energy on nonwoven webs. The results indicate that fibers modified by silicone-containing polymer additives showed the greatest increase in hydro-phylicity. Meltblown webs of PP and PET with selected additive also shared the same potential increase of hydrophilicity.

PTT (polytrimethylene terephthalate) (PTT) based meltblown and spunbonded webs have been produced by using Reicofil® Bi-Component Meltblown Line at TANDEC at the University of Tennessee and Reicofil® 3 Spunbonding system at Reifenhauser, Germany. The processability of meltblown and spunbonding in a wide range of operating windows was extensively investigated. The produced webs were characterized to optimize this process. It was found that the PTT grade studied is quite suitable for the meltblown and spunbonding process. The PTT/PP based bico meltblown webs showed enhanced barrier properties and heat resistance and the PTT spunbonded nonwovens showed advanced drapability and elastic recovery. Staple PTT fibers were also made into nonwovens using hydroentangling, thermobonding and needlepunching. Properties of these nonwovens were studied.