A.D. La Rosa

An oxygen index evaluation of flammability on modified epoxy/polyester systems

Abstract This article describes a study on flame retardancy conducted on a dual cure thermosetting system consisting of an epoxy resin, blended with an unsaturated polyester. Neat resin panels and glass-fibre reinforced composites were prepared utilising several structurally different flame-retardant (FR) additives. These materials were tested in order to determine the Limiting Oxygen Index (LOI), which is a measure of the fire performance properties of a given material. Particular attention was paid to the FR properties of compounds, which are free of halogen such as bromine, in the absence of antimony oxide. These compounds are based on phosphorous containing molecules.

New aromatic polyamide materials containing sulfone, ether and ketone linkages

Abstract Several aromatic polyamides were prepared from 4,4′-[sulfonyl bis( p -benzoyl)( p -phenyleneoxy)]dibenzoic acid with various diamines by the phosphorylation route. The polymers were characterized by elemental analysis, thermogravimetric analysis, differential scanning calorimetry and infra-red analysis. The polyamides, obtained in quantitative yield, possessed inherent viscosities in the range 0.3–1 dl g −1 and 10% weight loss in nitrogen and air were above 460 and 440°C, respectively. Most of the polymers were soluble in aprotic solvents. The effect of the structure on properties such as solubility and thermal behaviour were also studied.

Eco-Compatible Use of Olive Husk as Filler in Thermoplastic Composites

A study on the possibility of recycling waste materials, such as olive husk, the solid phase derived from an olive oil mill, in blend with thermoplastic polymers to produce new materials for manufacturer of, for example, containers and formworks, has been carried out. The present paper describes the methodology used for the preparation and the characterization of composite samples prepared by mixing various percentages of olive husk and polypropylene. A screening on the chemical-physical characteristics of the olive husk is reported, as well as a set of tests applied to evaluate the mechanical properties of the manufactured products obtained.

Flame-retarding properties of a new phosphorus-containing monomer used as hardener in an epoxy system

Abstract A new ortho-hydroxy-aryl-phosphonate additive was used to improve the flame resistance of an epoxy/anhydride system. Thermal, rheological, L.O.l. and SEM experiments were carried out to show that the P-additive acts not only as a flame retardant but also as a curing agent.

An esca study of new collagen-based bioartificial polymeric materials

The surface composition of films prepared from blends containing different percentages of pure soluble collagen and poly(acrylic acid) or poly(sodium vinylsulfonate), was analysed by ESCA. The results indicate that the content of collagen on the surface of the blends is higher than expected, and that such enrichment is more evident for the blends containing a lower percentage of collagen.

Pyrolysis of glass-hardened polyamides used in the automotive industry

Thermogravimetry and on-line flash pyrolysis–gas chromatography–mass spectrometry were used for studying thermal decomposition processes in filled polyamides deriving from used cars. The thermal decomposition of each polymer begins at about 350 °C and proceeds with a weight loss of 100% for the non-glass fibres, under nitrogen atmosphere. The analysis of the pyrolyzate compounds shows that from polyamide 66, the most abundant product volatile at degradation temperatures is cyclopentanone, while from polyamide 6 there is a considerable yield of ε-caprolactam.

LCA of fibre-reinforced composites

This chapter discusses the utility of applying the life cycle assessment (LCA) methodology to fibre-reinforced composites. The chapter first introduces the main advantages of shifting from traditional petroleum-derived polymer composites to bio-derived polymer composites. LCA methodology is then described as a useful tool to evaluate the environmental impacts of products and processes. Some case studies are reported on LCA of polymer composites used in the automotive and building sectors.

A Further Study on New Halogen-Free Flame-Retarded Thermosets

The present work is a further development of a study already started on modified epoxy/polyester systems /1/. In previous studies, attempts to incorporate covalently bonded phosphorous atoms in epoxy resins were carried out in our laboratory. Neat panels and glass-fibre (GF) reinforced composites were prepared using halogen free flame-retardant (FR) additives. These materials were tested on a cone calorimeter apparatus in order to evaluate the heat release rate (HRR) and the ignition time values for each FR formulation. LOI and UL94 tests were carried out. In the present paper, red phosphorous (Red P) together with aluminium oxide trihydrate (ATH) and glass fibre (GF) was found to be a good substitutive formulation to replace halogen based FR-additives.

4 – Life cycle assessment of biopolymers

The present chapter discusses the application of the life cycle assessment (LCA) methodology to biomass-derived polymers. The chapter first introduces the concept of biopolymers and the main advantages of shifting from traditional petroleum-derived polymers to biomass-derived polymers. LCA methodology is then described as a useful tool to evaluate the environmental impacts of products and processes. Some case studies are reported on LCA of biopolymers used in several sectors with a major focus on the building sector.

Modelling of contaminant migration in unsaturated soils

Laboratory studies are useful for understanding the behaviour of chemical contaminants in soil, although such investigations do not always relate directly to field conditions. This paper reports an application of a model in order to investigate the migration of nitrates through the soil. The model calibration was carried out using the experimental data obtained from two different soil samples collected in the countryside of Catania (Italy). The device used for laboratory scale study was a permeameter loaded with the soil samples; acqueous solutions containing different percentage of nitrate were used as chemical contaminant. Two software products, SEEP/W and CTRAN/W, are used in tandem to analyze the contaminant transport for unsaturated conditions: SEEP/W computes the water flow velocity, volumetric water content, and water flux; CTRAN/W uses these parameters to compute the contaminant migration. Unsaturated zone models are useful tools in predicting the effects of measures and can be used to optimise agricultural practice aiming to minimise the impact on the environment.