Tuesday, September 22

Acoustical materials often utilize nonwoven (or woven) materials as facings. The reasons for using these facings can range from acoustical benefits to physical properties, abuse resistance, fire performance, or aesthetics. This paper will review the acoustical benefits of facings and explore, through theory and test data, how to achieve acoustical performance goals through the use of facings in combination with acoustical materials or even through the use of nonwoven fabrics by themselves.

The WUFI^® heat and moisture modeling software (Fraunhofer-Institut für Bauphysik) is widely used in the building industry to evaluate the performance of building envelope systems. There is a database of insulating materials in the WUFI^® software which simulators use to model new applications. Unfortunately, the properties for some of these materials can deviate significantly from those of real world products. Thus, the modeling results may not represent a wall systems actual performance in the field. Field test walls using some novel materials and traditional fiberglass insulation materials were constructed in specific weather zones and test data were collected over a 6-month period. This paper will examine some of those test results and compare the WUFI^® simulation results with the walls actual performance.

In this paper, recent developments in formaldehyde-free thermosetting resin chemistry will be discussed. Materials of interest include both water-dispersed and water soluble resins. The strength of these resins, when coated on substrates, will be tracked as a function of thermal treatment. Strength development during thermal treatment will be discussed in the context of network formation due to a) chain entanglement /thermoplastic effects) as well as b) covalent bond formation /thermoset effects. Factors affecting water sensitivity will be discussed as well.

The fiber entanglements of durable nonwoven constructions are typically reinforced by an internal binder that is based on different types of latex polymer emulsions. While amino based crosslinking resins can be used to enhance the reinforcing properties of the binder, the choice of latex polymer chemistry substantially influences the physical properties of a cured nonwoven construction. In this paper, the impact of the selected polymer chemistry changes on the final properties of a cured nonwoven construction will be investigated.

The Voith HydroFormer is the ideal inclined wire former for long fiber paper and wet lay nonwoven products. Fibers with a length of 2 to 40 mm can be used to form a sheet with a homogenous fiber distribution.

The Multiply HydroFormer offers new opportunities for the versatile special paper market. With the multiply head box only one sheet forming process is needed to get a multilayer product. An individual fiber composition in each ply allows to influence the characteristic of the nonwoven product.

The presentation will give an overview about the multiply sheet forming process and shows current fields of applications.

U.S. cottons have to compete in the global marketplace. For this market, improved and fast response quality measurement systems are needed to assess the quality of cotton, to include new field and at-line quality measurements. These improved quality assessments can yield positive benefits to sustainability programs, to include assisting breeders in their decision-making on key production and harvesting actions. A critical cotton fiber quality and processing property is the fibers micronaire. Micronaire is an indirect measurement of the maturity and fineness (diameter) of the cotton fiber, and it is often determined in a laboratory environment with expensive laboratory testing equipment. Comparative evaluations were performed with a hand-held, portable NIR analyzer to determine the ability of portable NIR techniques to monitor micronaire and other critical cotton fiber properties in the laboratory, at-line, and in the field. With the portable instrument, NIR measurements of cotton can be performed directly on the cotton sample (cotton boll in the field; lint/fiber at the gin, mill, and laboratory). Initial evaluations established the optimal instrumental settings, operational conditions, measurement protocols, and sampling systems (laboratory, at-line, and field). Distinct spectral and micronaire differences were detected between cotton varieties and bolls with known differences. The NIR measurement was fast and easy to use.

Over the past decade, considerable interest has emerged in replacing conventional fossil fuel-based polymers with bio-derived polymers and with the materials capable to biodegrade in the ambient soil or marine environments. Recent discoveries in genetic engineering and commercialization of the resin manufacturing lead to the introduction of a new family of PHB copolymers, which are produced by the fermentation of corn or cane sugars or vegetable oil and satisfy both requirements on sustainability and biodegradability. The family of developed PHB based compounds consists of the grades with wide range of properties that could be matched to the specific requirements and processed using conventional plastics converting equipment. The PHB copolymers have been found to be very suitable for the production of the melt blown nonwovens. In this presentation we discuss the fiber properties in their relationship to the polymer rheology and processing conditions.

Polylactic acid (PLA) can be produced from plant sources such as corn, and PLA is totally biodegradable. As such, PLA is of great interest because of its green nature. We studied the melt spinning and melt blowing of PLA with the goal of improving the crystal structure, tenacity, and other properties of the fiber. High speed photography and infrared thermography were used to perform on-line measurements of fiber attenuation rate and fiber temperature. In parallel with these experiments, numerical simulations of the processes were done with a high speed computer. The model and the experiments gave similar results. In spinning, PLA behaves very similarly to PP, though there are some key differences. These differences must be considered if PLA is used to replace or supplement PP in melt spun and melt blown products

Recent application development has shown the ability to produce meltblown Ingeo fabrics. This new application provides an environmentally friendly option for nonwovens producers to meet convenience and performance needs for a range of applications. Process details and fabric data will be reviewed along with the benefits of using Ingeo PLA vs conventional materials.

The purpose of this research is to develop the next generation of biodegradable mulch fabric from polylactic acid (PLA) with the goal of applying a treatment to make it truly biodegradable in the field after use for the growing season, without leaving fragments. Meltblown 100% PLA 60 g/m2 nonwoven fabric was placed about 1.5 inches under two types of soil (typical soil and soil from an organic farm) in trays in a greenhouse with overhead misting of water. The fabric specimens were treated separately with 1) tap water (control), 2) compost, and 3) lime and were exposed in soil for 16 weeks. They will be tested for weight loss, tensile strength loss, and for molecular weight changes using GPC analysis, and will be examined by SEM for evidence of degradation. Furthermore, the soil will be analyzed to determine the composition to degradation products and the impact of the mulch on soil microorganisms