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There are several areas in which textiles have been highly desirable due to their specific and high performance for many industries and sectors including in civil engineering, automobile, medicine, filtration, and electronics. Polymer used has a significant effect on the properties of meltblown nonwovens. Polypropylene being the most commonly used polymer, very limited data have been reported on the polyethylene meltblown nonwovens which are desired due to their unique processing and performance advantages. In this study, we have investigated the effects of process variables, die temperature, air pressure, and die-to-collector distance on some characteristics of polyethylene meltblown nonwovens such as pore size, air permeability, hydrostatic head, and SEM analysis. It was observed that the variables have significant effects on the produced nonwovens, and many of the properties are comparable to those obtained with that of polypropylene meltblown webs. [ABSTRACT FROM AUTHOR]

Minerals have been widely added to polyolefins during film- or fiber-manufacturing process to improve the processibility as well as to enhance the product properties such as thermal conductivity, surface roughness, fabric filtration efficiency, and fabric capacity of oil absorbency. Titanium dioxide has been traditionally added in PET fibers as a delustrant to reduce their transparency for some applications, e.g. clothing materials. Calcium carbonate has recently been added in polymelt – spunbond and meltblown – fibers to increase the fiber processibility and to improve the fiber properties and hence to achieve their final performance. It is crucial that the adding quantity should be controlled so the fabric strength will not be adversely reduced. Calcium carbonate is frequently over-added in polymelt fibers to take the advantage in business trading by weight. A method is essential to determine the mineral content in the polymeric materials. While trying to use the volume of the fabrics displaced by liquid to determine the density of fibers fails, we successfully used buoyant force of the fabrics in a liquid to precisely determine the volume of the fibers and to use it to calculate the mineral content in spunmelt PP fabrics. A gadget was designed to incorporate with a balance to form a density balance for this research. It was observed that only a single layer but not multiple layers of fabric is a key point to accurately determine its buoyancy in the liquid. Multiple layers contributed to a relaxation of the bending forces at the folding lines of the fabric, which attributed to an error in measuring the buoyancy of the fabric. [ABSTRACT FROM PUBLISHER]

In this paper, spunbond, meltblown and spunbond–meltblown–spunbond (SMS) nonwovens made from polypropylene are analysed for liquid transport behaviour. The thickness, grams per square metre (GSM), porosity, fibre diameter, fibre orientation distribution and water contact angles of these nonwovens are measured. Vertical wicking with decane using tensiometry and water absorbency and spreading using gravimetric absorbency tester are reported. The equivalent pore radii of the nonwovens are deduced from the vertical sorption experiments using tensiometry. The sorption rate under vertical wicking and water spreading rates are faster along machine direction compared with that in cross‐direction due to preferential fibre orientation. The thickness of the nonwoven, fibre diameter and porosity play a vital role in transporting liquid. Thin nonwovens have poor vertical wicking and spreading rate. SMS web has poor absorbency behaviour mainly due to the inability of its top S‐layer to pull the liquid from the middle M‐layer. The measured water spreading lengths with respect to time are compared to the theoretical ones using a model developed by earlier researchers. This model reasonably predicts the spreading behaviour of nonwovens. [ABSTRACT FROM PUBLISHER]