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This article reports testing of the efficacy of five consolidants (sodium alginate, zinc alginate, Paraloid® B-72, TRI-Funori™, Methocel® A4C) used by conservators for consolidation. The consolidants were tested for potential use on deteriorated black-dyed plant fibres, specifically paru-dyed muka (iron-tannate dyed fibre from harakeke; New Zealand flax, Phormium tenax), building on previous experimental work. Paru-dyed test fibres were pre-aged (light, with UV) to simulate museum artefacts, and then consolidated, after which their colour stability, strength retention, and acidity were measured. Consolidated test fibres were then artificially light-aged (UV-filtered) to test the stability of the consolidants over time (10 MLux hours; UV-filtered light), with colour stability, strength retention, and acidity re-measured after this ageing stage. A full factorial experimental design with four factors was used for testing: dye type, consolidant type, consolidant concentration, and accelerated light-ageing. Data were analysed using generalised linear models (GLM) coupled with analysis of variance (ANOVA) and simple effects procedures to test for interactions between factors and determine significant differences. Overall, this study found that using criteria of pH, strength, colour stability, and visual properties, that 0.5% w/v Methocel® A4C™ in H2O and TRI-Funori™ 0.5% w/v in H2O were recommended for further exploration for use on deteriorated paru-dyed muka. [ABSTRACT FROM AUTHOR]

Due to good density specific mechanical properties and low carbon footprint, natural fibre-reinforced plastic composites made from fleeces and felts are frequently used as automotive interior parts. The industry targets further mass reduction. Following a biomimetic technology-pull approach, natural fibre-reinforced polypropylene plates with improved lightweight potential were produced using compression moulding. Best results were obtained for a sandwich structure with thin, unidirectional flax fibre layers surrounding a needle felt based core. It was inspired by the carapace structure of the red-eared slider Trachemys scripta elegans. The lay-up performed well, not only with a high density specific flexural stiffness of 2.33 GPa1/3 cm3/g, strength of 9.46 MPa1/2 cm3/g, and energy dissipation but also through less abrupt failure due to an asymmetric orientation of unidirectional fibres in the two face sheets. Combined with a mass-reduced needle felt as a core, this concept displays a promising and unconventional approach for further mass reduced, sustainable interior panels used as non-visible and visible design elements in the vehicle.

Active nanocomposite films based on soy protein isolates (SPI), microfibrillated cellulose (MFC) and clove essential oil (CEO) were developed, and the contribution of each component to the functionality of ensuing films was intended to elucidate. MFC with diameters of 50–60 nm, an average length of 485 ± 2 μm, a high aspect ratio of 8800 and 35.5% of cristalinity, was prepared from Phormium tenax fibers by mechanical treatment. Films were processed by casting from aqueous dispersions containing SPI, glycerol (as plasticizer), different MFC contents and the optional addition of CEO. All filmogenic dispersions exhibited a pseudoplastic flow behavior and formed homogeneous films. The addition of MFC reinforced the protein matrix, increasing the mechanical strength and Young's modulus of the films and improving their barrier properties to water vapor and oxygen. On the other hand, the addition of CEO caused some plastification effect of protein and nanocomposite matrix (mainly observed in the mechanical properties, solubility and water content) and a differential modification in the barrier properties, as the oxygen permeability increased and WVP decreased. Furthermore, it conferred important antioxidant properties and antimicrobial activity against bacteria related to foodborne diseases that increased with increasing MFC content in the formulation. Nanofibers seemed to favor the release of the active compounds of CEO probably due to the improved dispersion of CEO in nanocomposites through a higher amount of smaller droplets. These active nanocomposite films with antimicrobial and antioxidant properties are promising for the development of active food packaging. [ABSTRACT FROM AUTHOR]

Black-dyed artefacts are found in museums worldwide, many produced using an irontannate compound. Deterioration of iron-tannate dyed artefacts is an international preservation issue: in New Zealand the deterioration of paru (iron-tannate) dyed Māori textiles is widespread. This article reports experimental work testing the efficacy of sodium alginate, a consolidant developed for deteriorated paru-dyed muka (fibre from harakeke; Phormium tenax). The colour stability, strength retention, and acidity of paru-dyed muka consolidated with sodium alginate (0.25, 0.5, and 1% w/v in water) was tested pre- and post-artificial light ageing. This study found that sodium alginate had no negative effect on paru-dyed muka and in some cases provided benefit. Interestingly, the colour of parudyed muka is substantially more stable in UV-filtered light than previously recognised. Also microfading results were in agreement with visual assessments of colour change at 1 Mlux hour exposure, providing confidence in this relatively new technique to assess colour change. [ABSTRACT FROM AUTHOR]

Where does life live? What is alive? In modernist/dualist thinking, we might assume that life lives through cause and effect—an acting of someone onto something. When conceived through an Indigenous-Māori concept of mauri—life vitality— the immanence of living as a relational field is revealed. An ethical imperative to sustain the wellness of the life-field, mauri-ora, is concurrent with the concept of mauri. This paper philosophically probes the immanent and ethical conditions of this life-field and its relational sustenance as the very ground for design thinking. Here, I explore an architectural project, Te Uru Taumatua, as a case for thinking through mauri-ora (life-field)asimmanent ethics in relation to an evocation of ecological vitality. This project becomes a bridge for thinking immanent connections across Indigenous-Maori and contemporary ecological thinking. This paper argues that architecture’s role as an Anthropocenic actor creates the conditions necessary to instantiate socio-ecologically situated immanent ethicsasdesign ethics. What is fundamental to this approach is to reveal howecological designis a thinking manifest here, in this case study,asthe relation of mauri to mauri-ora. Here, Te Uru Taumatua helps to explore an understanding of mauri-ora as an immanent ethics which bridges (design) thinking and practice. [ABSTRACT FROM AUTHOR]

The objective of this study was to fabricate and assess the structure and mechanical performance of PLA reinforced by aligned discontinuous alkali treated natural fibre mats. The novel aspect of this work was in terms of composite processing, in particular, the use of fibre mats produced using a dynamic sheet former (DSF) wherein discontinuous treated fibres were aligned. Composites with different fibre weight contents were assessed using optical microscopy, scanning electron microscopy (SEM) and tensile testing. It was found that the fibres had a reasonable degree of alignment parallel to the DSF rotation direction together with good fibre dispersion. Tensile strengths of harakeke and hemp composites up to 101.6 MPa and to 87.3 MPa were achieved, approximately 90 and 60% higher respectively than PLA (53.9 MPa). It was also found that minimum and critical fibre volume fractions for harakeke and hemp fibre composites were lower than that found for injection moulded composites, due to better reinforcement efficiency obtained as a result of increased fibre alignment. [ABSTRACT FROM AUTHOR]

In many ecosystems food-web dynamics are driven by spatial and temporal variation in the availability of sugar resources, which form the primary or even exclusive dietary constituents for many species. Scale insects (Hemiptera) produce sugar-rich honeydew, which can be a keystone sugar source in honeydew ecosystems worldwide. In New Zealand, most previous research in honeydew ecosystems has been conducted in areas where herpetofauna are heavily suppressed by introduced predators. Consequently, little is known about potential trophic interactions between endemic lizards and scale insects. Korapuki Island is one of the few remaining locations in New Zealand where endemic scale insects and lizards survive in densities likely to be representative of prehuman conditions. We examined the relative importance of different sugar resources on Korapuki Island to Duvaucel's geckos (Hoplodactylus duvaucelii) and common geckos (Woodworthia maculatus). We recorded the abundance and morphometrics of geckos attending five sugar-producing plant species (two of which host honeydew-producing scale insects) three times daily along a fixed transect. Large numbers of Duvaucel's and common geckos were recorded nocturnally feeding on honeydew produced by the scale insect Coelostomidia zealandica (Coelostomidiidae). Duvaucel's geckos of all sizes and genders fed extensively on honeydew throughout the year, favouring ngaio (Myoporum laetum) trees with high scale insect infestations, but were seldom recorded at other sugar resources. In contrast, juvenile common geckos were infrequently recorded on honeydew-producing trees. Common geckos fed on a variety of other sugar resources, with all sizes and sexes abundant on nectar and sap of flax (Phormium tenax) and seasonally exploiting nectar of pohutukawa (Metrosideros excelsa). The strength of interactions between scale insects and geckos, particularly for the Duvaucel's gecko population on Korapuki Island, indicates the importance of honeydew in addition to more ephemeral sugar resources such as nectar. Accordingly, the re-establishment of honeydew-producing Hemiptera populations should be considered in future conservation and restoration plans. [ABSTRACT FROM AUTHOR]

Composites including short and randomly arranged Phormium tenax fibres in a polypropylene (PP) matrix (fibre content of 20, 30 and 40 wt%) were produced by twin-screw compounding and injection moulding. They have been characterised by tensile testing, scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results indicated that tensile modulus has been increased by reinforcing the matrix with growing amounts of fibres, whilst the effect on tensile strength had lower evidence. Fracture surface characterisation by SEM indicated that debonding and pull-out are prevalent, which suggests the need to optimise the interfacial bonding. Thermal characterisation results have shown that the main degradation peak for PP was slightly shifted to higher temperatures with the increasing fibre contents, thus improving the thermal stability of the composites. The introduction of fibres did not result in a significant variation in the position of the peaks for calorimetric analysis, except for the melting peak, which appeared lower for the composites with respect to the neat matrix. A slight increase in crystallinity was also measured. [ABSTRACT FROM PUBLISHER]

Different tissues in Phormium tenax leaves present different morphologies and mechanical properties according to the different roles or functions that they play during the plant life. This is an example of what is known as functional design, a concept which is used in different scientific fields. Four different ultrasonic techniques comprising air-coupling and gel coupling, longitudinal and shear waves, normal and oblique incidence and low (0.2 MHz) and high frequencies (2.25 MHz) have been employed to study these leaves. By changing these experimental conditions it is possible to propagate longitudinal and shear waves in the different tissues present in these leaves (spongy mesophyll, chlorenchyma and sclerenchyma fibres) and in different directions so it is possible to determine their ultrasonic properties (velocity and attenuation) and hence their main elastic mudulii. Additional analysis of microscopic images of the tissues permit to study the correlation between this elastic and ultrasonic tissues properties and main microscopic features like cell size and cell wall thickness, which are determined by the different function of these tissues. [ABSTRACT FROM AUTHOR]

Highlights: [•] Cellulose nanocrystals (CNC) were successfully extracted from Phormium tenax leaves. [•] Limonene was used as plasticizer for poly(lactic acid) (PLA) based formulations. [•] PLA_Limonene_CNC bio-nanocomposites were produced by a twin-screw microextruder. [•] The addition of limonene positively affects the mechanical properties of PLA. [•] The presence of plasticizer and CNC alters the degradation of PLA bio-nanocomposites. [ABSTRACT FROM AUTHOR]

Este trabalho tem como objetivo avaliar os sintomas das folhas na vida pós-colheita do Phormium tenax sobre efeito de diferentes tratamentos.

Highlights: [•] Cellulose nanocrystals (CNC) were extracted from natural Phormium tenax and Flax. [•] CNC were also extracted from commercial microcrystalline cellulose for comparison. [•] Natural fibres offered high levels of extraction efficiency. [•] Homogeneous distribution of CNC in PVA is observed and transparent films are obtained. [•] CNC promotes the crystallization of the PVA matrix improving its plastic response. [ABSTRACT FROM AUTHOR]

To study how pollinator composition and abundance influence reproduction ofPhormium tenax, we compared pollen deposition by bees and birds to unvisited flowers, and plant reproductive success and outcrossing rates in populations on island and mainland sites that vary in bird abundance. Bees deposited pollen on stigmas if stigmas were close to the anthers but deposited little pollen on stigmas of emasculated flowers, suggesting that they are largely depositing self pollen. Birds deposit pollen on both intact and emasculated flowers with well-exserted stigmas, suggesting they are depositing more outcross pollen. High frequencies of bird claw marks on inflorescences were associated with high fruit set, but not seed set. Seed set and seed outcrossing rates were positively correlated with the number of unique maternal allozyme genotypes in a population and seedlings also showed higher outcrossing rates than seeds, suggesting that genetic diversity, selfing and inbreeding depression limit reproductive success. These results highlight the interplay of pollination and breeding systems in determining plant reproductive success. [ABSTRACT FROM AUTHOR]

In the present study, Phormium Tenax fiber reinforced PLA composites were processed by injection molding and twin screw compounding with a fiber content ranging from 10 to 30 wt%. Three surface treatment methods have been used to improve the Phormium Tenax fiber-matrix interfacial bonding that are as follows: (1) aqueous alkaline solution, (2) silane coupling agent, and (3) a combination of alkaline and silane treatment. The mechanical, thermal and morphological properties of the resulting composites were investigated. The results have shown that the moduli of surface treated fiber reinforced composites are lower than the ones obtained for untreated composites (as a consequence of the decrease in fiber modulus caused by the chemical treatments) and no significant increase in strength was observed for any of the composites compared to neat PLA. SEM micrographs of composite fractured surfaces confirmed an improvement in the interfacial strength, which was insufficient nonetheless to significantly enhance the mechanical behavior of the resulting composites. Results from thermogravimetric analysis and differential scanning calorimetry suggest that surface treatment of Phormium affects the ability of PLA to cold crystallize, and the thermal stability of the composites at the different fiber contents was reduced with introduction of alkali and silane treated Phormium fibers. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals with an acicular structure ranged from 100 to 200 nm in length and 15 nm in width were extracted from Phormium tenax leaf fibres by acid hydrolysis. A two-step procedure for the extraction of nano-sized cellulose was studied and the obtained nanocrystals were characterized using morphological investigations (optical, scanning electron and atomic force microscopy), as well as physico-chemical characterization by Wide Angle X-ray Scattering, infrared spectroscopy and thermogravimetric analysis. A study of birefringence properties was also performed. The first chemical treatment leads to the production of holocellulose by the gradual removal of lignin, while the subsequent sulphuric acid hydrolysis process allows obtaining cellulose nanocrystals in an aqueous suspension. The results reported support the repeatability and the effectiveness of the procedure performed. Moreover, the high cellulose content of P. tenax fibre and their declining market interest, suggest the interest of this investigation and the possibility to use natural fibres for the production of a reinforcement phase to involve in the nanocomposite approach for industrial applications. [ABSTRACT FROM AUTHOR]

Abstract: This study reports the synthesis and mechanical properties of new inorganic polymer (geopolymer) composites unidirectionally reinforced with 4–10vol.% natural cellulose-based fibres (NZ flax, phormium tenax). The geopolymer matrix was derived from dehydroxylated kaolinite-type clay. The mechanical properties of the fibre-reinforced composites improve with increasing fibre content, achieving ultimate flexural strengths of about 70MPa at 10vol.% fibre content. This represents a significant improvement on the flexural strength of the unreinforced geopolymer matrix (about 5.8MPa), and all the composites show graceful failure, unlike the brittle failure of the matrix. Scanning electron microscopy was used to study the morphology of the fibre-matrix regions and a combination of thermogravimetric analysis (TGA) and thermal shrinkage measurements of these composites suggests that despite the formation of microcracks due to water loss from the geopolymer matrix, the fibres are thermally protected by the matrix up to 400°C. The flax fibres do not appear to be compromised by the alkaline environment of the matrix, suggesting new possible applications for these low-cost simply prepared construction materials. [Copyright &y& Elsevier]

Abstract: The effects of inorganic nitrogen (N) nutrition (NH4 +, NO3 − or both) at equimolar (0.5mM) concentration on growth, biomass allocation, mineral element concentration, N-uptake kinetics and nitrate reductase activity were assessed in hydroponically grown Cyperus laevigatus and Phormium tenax. Both species grew well with both NH4 + and NO3 − as the sole N source, but the mean growth rate of C. laevigatus (RGR=0.12d−1) was significantly higher than that of P. tenax (RGR=0.02d−1). However, the RGR of C. laevigatus was higher when supplied with NH4 +, either alone or in combination with NO3 −, than when supplied with NO3 − alone, whereas the RGR of P. tenax was indifferent to nitrogen source. The nitrogen uptake rate of C. laevigatus was generally higher (2–3-fold for NH4 + and 4–14-fold for NO3 −) than that of P. tenax in concert with its higher growth rate. Both species had higher uptake capacity and higher affinity for NH4 + than for NO3 −. The mean maximum uptake velocity (V max) for NH4 + was 99 and 41μmolg−1 root DM h−1 for C. laevigatus and P. tenax, respectively, as opposed to a V max for NO3 − of 24 and 3.4μmolg−1 root DM h−1 for C. laevigatus and P. tenax, respectively. P. tenax had significantly lower affinities for both NH4 + and NO3 − than C. laevigatus indicating that P. tenax are adapted to sites with relatively high N availability, as opposed to C. laevigatus, which via its high-affinity uptake systems can grow at sites with lower N availability. Both shoots and roots of both species had nitrate reductase activity, particularly when plants were fed with NO3 −. P. tenax seemed to be more sensitive to NH4 + nutrition than C. laevigatus since tissue concentrations of mineral elements were lower in roots of plants supplied with NH4 +. Our results suggest that the indifference to N nutrition provides C. laevigatus and P. tenax with the ability to grow well in periodically inundated areas with fluctuating and variable N sources. However, C. laevigatus may be better adapted than P. tenax to grow in permanently inundated soils with high NH4 + concentrations, whereas P. tenax may be better adapted to grow at high NO3 − condition. [Copyright &y& Elsevier]

Abstract: Solid-phase microextraction (SPME)–gas chromatography (GC)–mass spectrometry (MS) has been applied to the analysis of acetic acid and furfural that are emitted from the fibres of Phormium tenax (Xanthorrhoeaceae) [New Zealand flax] during degradation. Accelerated hydrothermal ageing of fibres of the Ruawai cultivar of P. tenax for 55 days at 70°C resulted in the production of acetic acid at a level greater or equal to 1.65mg g–1 fibre. This corresponds to only 8.5% of the acetyl groups present in the fibres. These groups are an important source of acetic acid, which is capable of damaging the fibres. The rate of production of acetic acid suggests that a heritage object made from the fibres of P. tenax, that was stored in damp ambient conditions, would undergo significant deterioration after a relatively short period. Other volatile products released during ageing included furfural, a series of short to medium chain aliphatic aldehydes that were derived from the oxidation of long chain unsaturated fatty acids on the fibres and a small group of products that were derived from carotenoids. The levels of furfural were determined to be approximately 0.75% of the potential production but at these levels, furfural could contribute to unpleasant odours from unventilated items. Fibres from six cultivars of P. tenax were found to release acetic acid and furfural all at the same rate. The levels of acetic acid that can be generated from these fibres are sufficiently high that low moisture levels and continuous change of air is required to minimize degradation of cultural objects that are made from these fibres and displayed in museum halls. [Copyright &y& Elsevier]

The disintegration patterns of composites produced by a melt compounding process using 0, 20, 30, and 40 wt % of Phormium tenax fibers in poly(lactic acid) (PLA) matrix were studied for a period of 40 days in composting conditions. The characterization of PLA and PLA/phormium composites included disintegration measurements, differential scanning calorimetry, FTIR analysis, thermogravimetric analysis, and scanning electron microscopy. The two controlling factors for disintegrability appeared to be the crystallinity of PLA and phormium fiber content: in general, the matrix tends to disintegrate completely before the 40 days and also phormium fibers undergo a substantial degradation during this period of time. Measurements taken at 10, 20, 30, and 40 days confirm that the disintegration process progresses steadily, though most of it takes place between 20 and 30 days. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Using the Raman imaging approach, the optimization of the plant cell wall design was investigated on the micron level within different tissue types at different positions of a Phormium tenax leaf. Pectin and lignin distribution were visualized and the cellulose microfibril angle (MFA) of the cell walls was determined. A detailed analysis of the Raman spectra extracted from the selected regions, allowed a semi-quantitative comparison of the chemical composition of the investigated tissue types on the micron level. The cell corners of the parenchyma revealed almost pure pectin and the cell wall an amount of 38-49% thereof. Slight lignification was observed in the parenchyma and collenchyma in the top of the leaf and a high variability (7-44%) in the sclerenchyma. In the cell corners and in the cell wall of the sclerenchymatic fibres surrounding the vascular tissue, the highest lignification was observed, which can act as a barrier and protection of the vascular tissue. In the sclerenchyma high variable MFA (4°-40°) was detected, which was related with lignin variability. In the primary cell walls a constant high MFA (57°-58°) was found together with pectin. The different plant cell wall designs on the tissue and microlevel involve changes in chemical composition as well as cellulose microfibril alignment and are discussed and related according to the development and function. [ABSTRACT FROM AUTHOR]

The objective of this study is to characterize the tensile properties of New Zealand flax (Phormium tenax) technical fibers to be used as potential reinforcement in polymer matrix composites. Single fiber tensile tests were performed at three gage lengths to assess the effect of gage length on tensile strength and Young’s modulus. The results were analyzed through a two-parameter Weibull distribution. The morphology, diameter, and fracture modes of P. tenax fibers were also characterized through optical and scanning electron microscopy. [ABSTRACT FROM AUTHOR]

Fibre properties may be an important source of information to identify, conserve and protect intraspecific diversity within culturally significant fibre plants such as harakeke (Phormium tenax, New Zealand flax). Māori weavers recognise differences in whītau * (fibre aggregate prepared using traditional practices) extracted from leaves of different harakeke cultivars. However, tensile properties of fibre aggregates are reportedly highly variable. The aim of this study was to investigate variation in fibre aggregate physical and mechanical properties among leaves harvested from different fans within two bushes representing different cultivars of harakeke. Tenacity, extension to maximum load, specific modulus and specific energy to maximum load of fibre aggregates differed between the bushes, and also among leaves within each bush. Leaf width and thickness were weakly correlated with fibre aggregate properties suggesting that wider, thicker leaves yield tougher and more pliable fibre aggregates. Variability among leaves differed according to the property measured, and was highest for fibre aggregate length and lowest for specific energy to maximum load. Although fibre aggregate tenacity (or strength) is commonly used to compare intra and interspecific fibre properties, specific modulus, extension at maximum load and specific energy to maximum load were all more appropriate for identifying intraspecific differences in harakeke fibre properties. [ABSTRACT FROM PUBLISHER]

Abstract: The present work investigates tensile and flexural behavior of untreated New Zealand flax (Phormium tenax) fiber reinforced epoxy composites. Two series of laminates were produced using the same reinforcement content (20wt%), arranged either as short fibers or quasi-unidirectional ones. Composites reinforced using quasi-unidirectional fibers showed higher modulus and strength both in tensile and flexural loading, when compared to neat epoxy resin. Short fiber composites, although still superior to epoxy resin both for tensile and flexural moduli, proved inferior in strength, especially as concerns tensile strength. These results have been supported by scanning electron microscopy (SEM), which allowed characterizing fiber–matrix interface, and by acoustic emission (AE) analysis, which enabled investigating failure mechanisms. In addition, thermal behavior of both untreated phormium fibers and composites has been studied by thermogravimetric analysis (TGA), revealing the thermal stability of composites to be higher than for phormium fibers and epoxy matrix alone. [Copyright &y& Elsevier]

Fifty-five accessions from the National New Zealand Flax Collection were subjected to genotyping using eight nuclear and two plastid simple sequence repeats (SSRs) and compared with a selection of predominantly wild Phormium plants. Several groups of plants with different names but identical SSR genotypes were found and these largely correspond with groups previously identified by analysis of their morphology. Maori cultivars are genetically diverse and include plants with interspecific (Phormium tenax × Phormium cookianum) hybrid origin. Genotyping supports historical and archaeological evidence that Phormium was taken to the subantarctic islands from southern New Zealand by sealers, and probably from the Chatham Islands by Maori and Moriori. As well as such tests of relatedness among Phormium selections, our markers provide opportunities to study the process of speciation, evolution and interspecific hybridization in Phormium. [ABSTRACT FROM AUTHOR]

Abstract: Most plastic packaging products are discarded after a single use resulting in an abundant supply of waste plastics. Natural fibres are light in weight, abundant and inexpensive. The stiffness and strength of polymers have been shown to improve with the incorporation of natural fibres. Hence, composite materials made of natural fibres and waste plastics would result in the reduction of plastic wastes and the use of fibres from renewable resources. Composite specimens and sheets consisting of fibres from the New Zealand flax plant, phormium tenax or Harakeke as it is known in Maori, and waste plastics have been produced through screwless extrusion followed by injection moulding. The tensile and impact properties of these composites have been determined. The formability of these composites has been assessed through thermoforming. [Copyright &y& Elsevier]