Biocomposites

Bio-composites represent an interesting solution for replacing fiber-glass in yachts, with the aim of increasing the
environmental sustainability of the nautical sector. This replacement is already occurring in several industrial sectors,
from building to automotive. However, the nautical field seems reluctant in embracing this innovation; reasons might
be found in the lack of technical references describing the bio-composite boat construction methods and the durability
of the yacht within time.
The production of a 4.6 m flax-epoxy and balsa wood racing sailboat is here described. The final aim of the
paper is providing boat designers and manufacturers with the methods to design and construct a bio-composite craft.
Tensile tests were performed on several specimens to obtain the mechanical properties of different fiber batches. Resin
absorption tests were conducted to select the natural core and surface treatment, to minimize the final weight of the
sandwich laminate. Finally, a specific multi-step infusion technique was developed to manufacture the hull and deck,
limiting the boat final weight to 65 kg. After four years from the launch, the boat neither shows structural failure nor
damage. This is considered a good test and indicates interesting perspectives for the applicability of bio-composites
into the nautical recreational field.

In the circular economy, bio-based plastics or bioplastics as emerging innovative materials are increasingly being used in many industries from packaging to building materials and agricultural products to electronic and biomedical devices, there is an increasing research on the evaluation of bioplastics in architecture, both as a material or as a design element in interior design. Therefore, this article is a step towards understanding the importance of bioplastic materials in the circular economies and in architecture, regarding the negative carbon footprint and long-term environmental effects of fossil-based plastics.

RESUMO​ : Este trabalho objetiva prospectar o potencial de produtos de origem biotecnológicas no design de produtos sustentáveis. Neste caso, tratamos do cultivo da celulose bacteriana obtida da Kombucha, uma bebida probiótica milenar. Utilizamos três métodos de pesquisa nesta prospecção: primeiro, nós adotamos a pesquisa exploratória, onde são apresentados os descritores associados ao termo Kombucha e celulose bacteriana; segundo, adotamos a pesquisa descritiva fazendo-se uso de gráficos e tabelas sobre o panorama na qual a pesquisa se insere, com apresentação de informações de ordem qualitativa e quantitativa; terceiro, pesquisa de abordagem explicativa que através dos experimentos práticos possibilitou a assimilação dos meios e métodos adotados na produção da celulose bacteriana. São apresentados os métodos base e diferentes técnicas utilizados para o processo de fabricação da celulose bacteriana, pós tratamentos e acabamentos e os primeiros experimentos práticos e os resultados da pesquisa em andamento. Palavras-chave​ : Ecodesign, biomateriais, biotecnologia, sustentabilidade, materiais e processos​ ​ de​ ​ fabricação. ABSTRACT​ : ​ This work aims to prospect the potential of products of biotechnological origin in the design for sustainable products. In this case, we deal with the cultivation of bacterial cellulose obtained from Kombucha, a milenar probiotic drink. We used three research methods in this prospection: first, we adopted the exploratory research, which describes the descriptors associated with the term Kombucha and bacterial cellulose; second, we adopted the descriptive research using graphs and tables on the panorama in which the research is inserted, with the presentation of qualitative and quantitative information; third, a explanatory research approach that allowed the assimilation of the means and methods through the practical experiments adopted in the production of bacterial cellulose. We present the basic methods and different techniques used for the bacterial cellulose manufacturing process, treatments and finishes and the first practical experiments and the results​ ​ of​ ​ the​ ​ research​ ​ in​ ​ progress.

Biopolymer composites for tensile testing were fabricated according to the American Society for Testing Materials, ASTM D638-10, using poly lactic acid (PLA) as the matrix material and varying volume percentage of heat treated and untreated luffa fiber as the reinforcement material. To achieve the composite materials with the highest tensile strength, optimization of the use of hot press machine for fabrication of composite specimens was given high importance. While optimizing the use of hot press machine, various parameters were considered. These parameters included processing temperature, processing time and cooling time. Combinations of varying magnitudes of these parameters were used to find the optimum processing method. The optimized method was then used to produce PLA – luffa composites. The fiber – matrix interface adhesion was studied using scanning electron microscope (SEM). The results show that composites made with heat treated fibers have higher tensile strength and better interfacial adhesion when compared with the tensile strength of composites made with untreated fiber.  Heat treated fibers showed a remarkable improvement in the tensile strength of the biocomposites, which may be used for a variety of applications in the orthopedic field.

Composite materials, based on renewable and biodegradable natural fibers, derived from agricultural waste and wood industry residues, are increasingly utilized in a wide variety of applications. These products represent an ecological and inexpensive alternative to the traditional petroleum-based materials, as they significantly decrease the use of fossil fuels and reduce the greenhouse gas emissions. In addition, these materials have good mechanical properties and require lower consumption of energy for their production. On the other hand, wood-based industries and agriculture produce significant amounts of organic waste and residues which are still underutilized, as low value energy resources and organic waste is commonly disposed of by some of the traditional waste management techniques, such as landfilling, anaerobic digestion or composting. The use of organic agricultural and wood industry waste and residues in production of natural fiber-reinforced polymer composites (NFPCs) is an environmentally friendly, sustainable and economical alternative. This paper represents a review of the possibilities for application of organic waste and residues as reinforcements or additives in NFPCs on the basis of the existing scientific information in the respective field.

This research work is concerned with the development of unsaturated polyester composites reinforced with betelnut fibers. Moreover, the fibers were chemically modified by sodium hydroxide and its effects on the fiber/matrix interaction were also evaluated. Raw and chemically modified fibers have been used in different proportions for the preparation of these composites. The optimization of fiber proportions has been done in term of their tensile strength. The sodium hydroxide treatment effect of fibers was verified by FTIR analysis and the fibers morphological aspects of fibers by SEM. Likewise, the sound absorption coefficient of composites were studied using impedance tube method. The thermal analyses of composites were made using Thermogravimetric analysis. Compared with untreated fiber composites, there was an improvement in the tensile strength of the treated fiber composites. SEM micrographs of betelnut fiber surface revealed the rough and perforated surface of fibers. Whereas, the cross sectional of the betelnut fibers showed the bigger lumen structures. The sound absorption coefficients of composites increased as the frequency increased and thicker composites appeared to perform better than those of thinner ones. The thermal stability of the treated fiber composites was found to be higher than that of untreated fiber composites.

This paper was focusing on effect of filler content and 3-aminopropyltriethoxysilane (3-APE) coupling agent on the mechanical properties, thermal properties and morphology of polylactic acid (PLA)/ coconut shell powder (CSP) biocomposites. It was found that the increasing of CSP content was decreased the tensile strength and elongation at break of PLA/CSP biocomposites. However, incorporation of CSP increased the modulus of elasticity of PLA/CSP biocomposites. The tensile strength and modulus of elasticity of PLA/CSP biocomposites were enhanced by presence of 3-APE, which attributed to improvement of the filler-matrix interaction. The thermal stability of PLA/CSP biocomposites increased with the filler content and it was improved by 3-APE treatment. Meanwhile, the present of CSP increased the glass transition temperature (Tg) and crystallinity (Xc) of PLA/CSP biocomposites at 30 php of filler content. After 3-APE treatment, Tg and Xc of PLA/CSP biocomposites increased due to the improve of the interfacial bonding. The peak of temperature of crystallization (Tc) presence in PLA/CSP biocomposites indicated the nucleating effect of CSP. Melting temperature (Tm) and Tc of PLA/CSP biocomposites was not significantly affect by filler content and 3-APE. PLA/CSP biocomposites treated with 3-APE was shown better filler-matrix interaction and it was confirmed through SEM micrograph.

Coconut shell is one type of lignocellulosic fillers abundance in Malaysia. In this research, coconut shell powder (CSP) was incorporated with polylactic acid (PLA) by melt compounding to produce PLA/CSP biocomposites. The acrylic acid was used in filler surface treated to improve the properties of PLA/CSP biocomposites. The effects of filler content and acrylic acid on the mechanical properties, thermal properties and morphology of PLA/CSP biocomposites were investigated. The result show, PLA/CSP biocomposites were decreased in tensile strength and elongation at break with increasing CSP content. Alternately, PLA/CSP biocomposites were shown increment in modulus of elasticity and thermal stability with increasing of filler content. Surface treatment by using acrylic acid enhanced filler-matrix interaction, indicates higher tensile strength, modulus of elasticity and thermal stability of PLA/CSP biocomposites and it better interfacial interaction was confirm through SEM micrograph

Evergrowing  concerns  related  to  sustainability  and ecology  have  been  the  key  driving  forces for  developing  bio-based  plastics,  especially  for  single-use  packaging applications, where biodegradability is an advantage. Automotive applic
ations are however much more challenging as durable bioplastics are expected to meet very demanding requirements, such as high thermo-mechanical  performance  at  both  very  short  term  (e.g.  impact)  and  very  long  term  (e.g.  creep, fatigue)  often  coupled  to  chemical  resistance  to  aggressive  automotive  fluids.  The  present
chapter focuses on the main classes of thermoplastic and thermosetting bioplastics and natural fiber-reinforced bioplastics, also called biocomposites, with current or emerging interest for the modern  car  industry.  It  points  out  the  great  potent
ial  of  these  renewable  materials  and  their expected  future  evolution,  without  forgetting  to  mention  their  present  drawbacks  and  the necessary  improvements  for  enhancing  their  durable applications  in  automotive  and  related sectors.

In recent years, extensive studies have been carried out on natural fiber reinforced thermoplastics due to their low cost, high specific properties, simple fabrication methods, biodegradable nature and diverse applications touching all commercial sectors. The challenge is to make composites with properties that are not overly compromised by the use of low technology. In this work, we review the performances of these resources, that is, wheat flour/wheat husk/wheat grain. By adding natural fibers, composites are also obtained by extrusion process. These composites exhibit performances which allow their use only for short duration. The mechanical, morphological, chemical, water absorption and thermal properties of biocomposites were studied.

Malaysia has more than 50 species of bamboo, but few that are utilized commercially. In this study, the physical properties of two of the most popular bamboo species in Malaysia, Gigantochloa scortechinii and Bambusa vulgaris, were evaluated. Moisture content (MC) and shrinkage variation at different height sections at both nodal and internodal categories of the bamboo culm were investigated. A comparison between the height sections and between the nodal and internodal categories, as well as between the species, was carried out. Results indicated a trend of decreasing MC along the culm from base to top, though the difference was not statistically significant. It was also observed that radial shrinkage was slightly greater than tangential shrinkage and was much greater than shrinkage in the longitudinal direction. Nodes appeared to have lower MC and a higher percentage of shrinkage compared to internodes. The shrinkage pattern of the two species of bamboo showed a small radial-to-tangential ratio of 1.15:1, which may have contributed to the dimensional stability of bamboo.

In this study, HP/ENR25 blends were prepared in aqueous solution with different hydrophilic polymers for rubber glove donning coating application. HP/ENR25 blend films were prepared using cast films technique to investigate the film formation prior to coating onto rubber
glove. The films surface morphology was characterised using Scanning Electron Microscopy (SEM) and Light Microscopy (LM). The microscopy results showed that coherence film formation can be obtained even though the PVA/ENR and PAA/ENR25 blends were immiscible. The
preliminary evaluation of coating onto rubber latex film indicated that PVP/ENR25 blend is feasible as coating material.

This  research  presents  an  alternative  material  that  follows  innovative  and sustainable standards constituted by the union of the gelatinized starch ma-trix  with  paper  waste  as  load.  Since  starch  and  paper  are  hydrophilic  nature,  limitations  in  the  applications  of  this  biocomposite  may  occur  if  no  barrier  is  created  to  restrict  moisture  absorption.  For  this,  waterproofing  tests  were  per-formed  to  analyze  the  behavior  of  the  material  in  relation  to  water  absorption  (2 and 24 hours) with four different waterproofing agents applying one, two and three  layer.  Satisfactory  results  were  obtained  from  the  second  coat  in  2  h  and  third coat in 24 h with the polyurethane based waterproofing agents. Therefore, comparing to the other waterproofing agents tested, and searching for more sustainable results, it can be concluded that the polyurethane-based waterproofing agent of vegetable origin proved to be the one that best meets the objectives of this research.