Composites science and technology

Over the coming few decades bioplastic materials are expected to complement and gradually replace some of the fossil oil based materials. Multidisciplinary research efforts have generated a significant level of technical and commercial success towards these bio-based materials. However, extensive application of these bio-based plastics is still challenged by one or more of their possible inherent limitations, such as poor processability, brittleness, hydrophilicity, poor moisture and gas barrier, inferior compatibility, poor electrical, thermal and physical properties. The incorporation of additives such as plasticizers into the biopolymers is a common practice to improve these inherent limitations. Generally, plasticizers are added to both synthetic and bio-based polymeric materials to impart flexibility, improve toughness, and lower the glass transition temperature. This review introduces the most common bio-based plastics and provides an overview of recent advances in the selection and use of plasticizers, and their effect on the performance of these materials. In addition to plasticizers, we also present a perspective of other emerging techniques of improving the overall performance of bio-based plastics. Although a wide variety of bio-based plastics are under development, this review focuses on plasticizers utilized for the most extensively studied bioplastics including poly(lactic acid), polyhydroxyalkanoates, thermoplastic starch, proteinaceous plastics and cellulose acetates. The ongoing challenge and future potentials of plasticizers for bio-based plastics are also discussed.

/pdf/progress-in-bio-based-plastics-and-plasticizing-32wsg84g03.pdf

Progress in bio-based plastics and plasticizing modifications

Evidence of microplastics in samples of zooplankton from Portuguese coastal waters.

https://www.utm.my/bactec/files/2015/01/Process-Biochemistry-venil-2013.pdf

Bacterial pigments and their applications

Two decades after the introduction of matrix assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI), soft ionization mass spectrometry represents a powerful toolset for the structural investigation of synthetic polymers. The present review highlights the current state-of-the-art, covering the latest developments of novel techniques, enabling instrumentation as well as the important applications of soft ionization MS from the beginning of 2008. Special attention is paid to the role that soft ionization MS has played in the mechanistic investigation of radical polymerization processes since 2005. © 2010 The Royal Society of Chemistry.

Mass spectrometry in polymer chemistry: A state-of-the-art up-date

Although oil remains an important binding medium in artists' paints, today's synthetic resins are being used with increasing frequency. This was true during much of the twentieth century, when artists such as David Alfaro Siqueiros, Jackson Pollock, and Pablo Picasso used commercial or industrial paints based on synthetic resins. The growing popularity of synthetic resin materials carries important implications for the conservation, preservation, and treatment of modern art. This volume outlines the techniques that are currently employed to analyse the synthetic resins used in modern painting materials, such as pyrolysisgas chromatography - mass spectrometry, Fourier Transform infrared spectroscopy, and direct temperature - resolved mass spectrometry.

Analysis of modern paints

Cellulose acetate, developed about 100 years ago as a versatile, semisynthetic plastic material, is used in a variety of applications and is perhaps best known as the basis of photographic film stock. Objects made wholly or partly from cellulose acetate are an important part of modern and contemporary cultural heritage, particularly in museum collections. Given the potential instability of the material, however, it is imperative to understand the aging mechanisms and deterioration pathways of cellulose ester plastics to mitigate decomposition and formulate guidelines for storage, exhibition, and conservation. One important aspect of this process is the ability to fully characterize the plastic, because variations in composition affect its aging properties and ultimate stability. In this Account, we assess the potential of a range of analytical techniques for plastics made from cellulose acetate, cellulose propionate, and cellulose butyrate. Comprehensive characterization of cellulose ester plastics is best achieved by applying several complementary analytical techniques. Fourier-transform IR (FTIR) and Raman spectroscopy provide rapid means for basic characterization of plastic objects, which can be useful for quick, noninvasive screening of museum collections with portable instruments. Pyrolysis GC/MS is capable of differentiating the main types of cellulose ester polymers but also permits a richly detailed compositional analysis of additives. Thermal analysis techniques provide a wealth of compositional information and thermal behavior. Thermogravimetry (TG) allows for quantitative analysis of thermally stable volatile additives, and weight-difference curves offer a novel means for assessing oxidative stability. The mechanical response to temperature, such as the glass transition, can be measured with dynamic mechanical analysis (DMA), but results from other thermal analysis techniques such as TG, differential scanning calorimetry (DSC), and dynamic load thermomechanical analysis (DLTMA) are often required to more accurately interpret the results. The analytical results from this study form the basis for in-depth studies of works of art fabricated from cellulose acetate. These objects, which are particularly at risk when stored in tightly sealed containers (as is often the case with photographic film), warrant particular attention for conservation given their susceptibility toward sudden onset of deterioration.

Application of Chemical and Thermal Analysis Methods for Studying Cellulose Ester Plastics

This paper describes the application of pyrolysis–gas chromatography–mass spectrometry (PyGCMS) to the characterization of an extensive range of synthetic paint types. Household and industrial pain...

The analysis of synthetic paints by pyrolysis–gas chromatography–mass spectrometry (PyGCMS)

Synthetic organic pigments have been manufactured since the latter part of the 19th century. Thousands of these pigments have been introduced for a variety of applications, including paints, printing inks, and the coloration of plastics and textiles. Many synthetic organic pigments are azos, containing the azo linkage (−N=N−). Newer classes of synthetic organic pigments have been introduced to overcome limitations of poor lightfastness or solvent fastness(bleed resistance) exhibited by some of the earlier pigments. This paper reviews the major classes of synthetic organic pigments in terms of their structures, physical properties, and specific applications. These classes include arylide yellows, diarylide yellows, β-naphthols, naphthols, benzimidazolones, disazo condensation pigments, pyrazolones, nickel azo yellow, phthalocyanines, quinacridones, perylenes and perinones, isoindolinone and isoindoline pigments, triarylcarbonium pigments, diketopyrrolo-pyrrole pigments, thioindigoids, and several m...

A Review of the Classes, Structures, and Methods of Analysis of Synthetic Organic Pigments

Acrylic emulsion (or more accurately dispersion) paints present major challenges to conservators, yet remarkably few studies of these materials have been published. Although frequently associated with paintings, these paints are also encountered on other supports, such as paper, textiles, objects and walls. The intent of this paper is to present much of the conservation information that does exist in a concise format to expedite much needed further discussion and research by conservators, paint manufacturers and artists. Brief descriptions of the development and analysis of acrylic emulsion paints are given, but the focus of this review is on conservation concerns, in particular issues surrounding the properties of paints, aging and cleaning.

Tom Learner

Papers

Analysis of modern paints

Application of Chemical and Thermal Analysis Methods for Studying Cellulose Ester Plastics

The analysis of synthetic paints by pyrolysis–gas chromatography–mass spectrometry (PyGCMS)

A Review of the Classes, Structures, and Methods of Analysis of Synthetic Organic Pigments

Conservation concerns for acrylic emulsion paints