Rethinking of toiletries rigid bottles for recycling improvement.

Rethinking of plastic rigid shampoo bottles based on "Design for the Environment" concepts is proposed. Bottles of most consumed shampoo brands with different capacities were selected. Bottle weight/capacity ratio was assessed and compression mechanical properties were evaluated. Oversizing of bottles and high amounts of material used in caps only for aesthetic purposes was proved. The analysis confirmed the need to change marketing strategies based on aesthetic attractiveness by an ecodesign based on functionality and sustainability aspects. The use of single material for the overall bottle is recommended, and it seems that HDPE is more suitable as it is appropriate to make all bottle parts, is recyclable, and has a low price/performance relationship. From a marketing point of view, a proper ecodesign would lead to a paradigm shift from an aesthetic approach to a sustainable one, in line with the environmental awareness of today's consumer.

Analysis of the relationship between the amount and type of MSW and population socioeconomic level: Bahía Blanca case study, Argentina.

The amount and type of municipal solid waste (MSW) in Bahía Blanca (Argentina) were assessed and correlated with population socioeconomic level. In this sense, seven areas with different quality of life were selected. In addition, a parallel study on a control area was performed and validated for obtaining a representative result to provide analogous conclusions for the whole city. From this study, a combination of sorting methodologies is proposed in order to reduce the actual amount of waste sent to landfill. If these methodologies are implemented in Bahia Blanca city, MSW in landfill could be reduced at least 80%. The proposed strategy is to combine waste sorting at source and at destination. An alternative separation at source could be proposed as follows: packaging (including plastic, cans and Tetra Pak), other plastics, paper and glass. The rest of MSW could be included in a container which would be collected daily or three times a week without changing inhabitants' habits and promoting their collaboration. Then, it could be separated at destination for waste-to-energy, composting, and biogas obtaining. Residuals from incinerators and biogas/composting plants would be sent to landfill. On the other hand, regarding the relationship between the proposed strategy and population quality of life, obtained results from this study could be useful to size and to efficiently locate disposal bins/containers for source separation as well as to redesign routes of municipal solid waste collection. Also, this strategy allows to add value to different components of MSW, improving working conditions of waste workers and creating new jobs in Bahia Blanca city.

Crystalline morphology of thermoplastic starch/talc nanocomposites induced by thermal processing.

A structural study about the changes induced by plasticization of native corn starch was carried out in this work. The influence of talc nanoparticles presence during starch thermal processing was also evaluated. Macroscopic observation of the granules appearance evolution during melt-mixing and thermo-compression was supported by a theoretical description related to these processing methods. Melt-mixing induced a polymorphic transformation from A- to Vh-type and a reduction in the degree of crystallinity. Homogenous appearance of the plasticized starch was in accordance to the disruption of granules integrity, evidenced by SEM. This observation agreed to the distinctive XRD pattern of plasticized starch from unprocessed granules. Talc incorporation did not require the adjustment of processing parameters in order to obtain a homogenous thermoplastic material, with an adequate particles distribution within the matrix. Regardless talc presence, plasticized starch presented a Vh-type crystalline structure. Thermo-compression led to particles alignment promoted by talc laminar morphology.

Compatibilization of HIPS/ABS blends from WEEE by using Styrene-Butadiene Rubber (SBR).

The aim of this work is to develop compatibilization strategies for High Impact Polystyrene (HIPS)/ Acrylonitrile-Butadiene-Styrene (ABS) blends from WEEE in order to add value to these recycled plastics by improving their mechanical performance. Results from a screening study of HIPS/ABS blends compatibilization by the addition of Styrene-Butadiene Rubber (SBR) are presented. Two different weight proportion of HIPS/ABS physical blends were analyzed, 80/20 and 20/80, with three different concentration of SBR: 2, 10 and 20 wt%. Compatibilization efficiency was analyzed from an accurate thermal and mechanical analysis, by comparing each physical blend and corresponding compatibilized blends with SBR. Results were discussed relating glass transition changes with mechanical performance, both aspects were interpreted in terms of blend morphology. Phase and fillers dispersion and distribution as well as SBR amount and its interaction with each phase were accurate analyzed. Compatibilization of HIPS/ABS blends from WEEE with the addition of SBR is effective in blends with HIPS as main component. With the addition of 2 wt% of SBR, strength and toughness have notably increased respect to the corresponding physical blend, 244% and 186% respectively. From this screening study is possible to infer that SBR is a sustainable and efficient compatibilizer of HIPS rich blends allowing to obtain a final blend that can be used as a replacement material of separated resins from WEEE.

Process Window for Direct Recycling of Acrylonitrile-Butadiene-Styrene and High-Impact Polystyrene from Electrical and Electronic Equipment Waste.

The aim of this paper is to assess recycling process window of ABS (Acrylonitrile-Butadiene-Styrene) and HIPS (High impact Polystyrene) from WEEE (waste from electrical and electronic equipment) through a final properties/structure screening study on their blends. Main motivation is to evaluate which amount of one plastic WEEE can be included into the other at least keeping their properties. In this sense, a wider margin of error during sorting could be admitted to obtain recycling materials with similar technological application of recycled ABS and HIPS by themselves. Results are discussed in terms of final blend structure, focusing in the interaction, within blends, of copolymers phases and fillers presents in WEEE. The comparative analysis of mechanical performance and morphology of HIPS/ABS blends indicates that the addition of 50wt% HIPS to ABS even improves 50% the elongation at break maintaining the strength. On the opposite, HIPS maintains its properties with 20wt% of ABS added. This study allows enlarging composition process window of recycling plastic WEEE for similar applications. This could be a sustainable way to improve benefit of e-scrap with low costs and easy processability. In consequence, social interest in the recycling of this kind of plastic scrap could be encourage from either ecological or economical points of view.

Recycling of mixed plastic waste from electrical and electronic equipment. Added value by compatibilization.

Plastic waste from electrical and electronic equipment (WEEE) grows up exponentially fast in the last two decades. Either consumption increase of technological products, like cellphones or computers, or the short lifetime of this products contributes to this rise generating an accumulation of specific plastic materials such ABS (Acrylonitrile-Butadiene-Styrene), HIPS (High impact Polystyrene), PC (Polycarbonate), among others. All of they can be recycled by themselves. However, to separate them by type is neither easy nor economically viable, then an alternative is recycling them together as a blend. Taking into account that could be a deterioration in final properties, to enhance phase adhesion and add value to a new plastic WEEE blend a compatibilization is needed. In this work, a systematical study of different compatibilizers for blends of HIPS and ABS from WEEE was performed. A screening analysis was carried out by adding two different compatibilizer concentration (2wt% and 20wt%) on a HIPS/ABS physical blend 80/20 proportion from plastic e-waste. Three copolymers were selected as possible compatibilizers by their possible affinity with initial plastic WEEE. A complete characterization of each WEEE was performed and compatibilization efficiency was evaluated by comparing either mechanical or morphological blends aspects. Considering blends analyzed in this work, the best performance was achieved by using 2% of styrene-acrylonitrile rubber, obtaining a compatibilized blend with double ultimate strength and modulus respect to the physical blend, and also improve mechanical properties of initial WEEE plastics. The proposed way is a promise route to improve benefit of e-scrap with sustainable, low costs and easy handling process. Consequently, social recycling interest will be encouraged by both ecological and economical points of view.

Use of talc as low-cost clarifier for wastewater.

Talc is proposed as a low-cost mineral for wastewater clarification. In this sense, adsorption of methylene blue (MB) from aqueous solutions was studied comparatively by using sepiolite (qualified as very good adsorbent) and two talc samples with different particle size and purity degree. The MB adsorption was assessed by determining remnant dye in the supernatant using UV-vis spectroscopy and by detecting dye adsorbed on mineral samples through thermogravimetric analysis and infrared spectroscopy. Both isothermal curves and kinetic studies demonstrate that talc is a good dye adsorbent. Particularly, with dye concentrations similar to those of textile wastewater, talc was demonstrated to adsorb the same dye content of sepiolite at similar times. Natural talc could be employed as a low-cost alternative in wastewater treatment for the removal of cationic dyes.

Glass Fiber Reinforced Polypropylene Mechanical Properties Enhancement by Adhesion Improvement.

Glass fibers (GF) are the reinforcement agent most used in polypropylene (PP) based composites, as they have good balance between properties and costs. However, their final properties are mainly determined by the strength and stability of the polymer-fiber interphase. Fibers do not act as an effective reinforcing material when the adhesion is weak. Also, the adhesion between phases can be easily degraded in aggressive environmental conditions such as high temperatures and/or elevated moisture, and by the stress fields to which the material may be exposed. Many efforts have been done to improve polymer-glass fiber adhesion by compatibility enhancement. The most used techniques include modifications in glass surface, polymer matrix and/or both. However, the results obtained do not show a good costs/properties improvement relationship. The aim of this work is to perform an accurate analysis regarding methods for GF/PP adhesion improvement and to propose a new route based on PP in-situ polymerization onto fibers. This route involves the modification of fibers with an aluminum alkyl and hydroxy-α-olefin and from there to enable the growth of the PP chains using direct metallocenic copolymerization. The adhesion improvements were further proved by fragmentation test, as well as by mechanical properties measurements. The strength and toughness increases three times and the interfacial strength duplicates in PP/GF composites prepared with in-situ polymerized fibers.

On the genus Panstrongylus Berg 1879: evolution, ecology and epidemiological significance.

The genus Panstrongylus is currently composed of 13 species, several of which are involved in the transmission of Trypanosoma cruzi to humans in South and Central America. Some species exhibit minor morphological differences possibly associated with adaptation to different silvatic ecotopes or domestic environments. We present a distillation of past and recent literature pertaining to the biology of this group. In particular, we summarise the current status of the genus according to systematic and recent phylogenetic studies. In light of recent evidence suggesting polyphyly/paraphyly of the genus we have investigated the possible mechanisms of morphological convergence/divergence. By assessing postembryonic ontogeny we reveal that the distinctive head shape of Panstrongylus can be derived from a Triatoma-like head late in development. A comprehensive phylogenetic study is therefore required to elucidate their relationship with Triatoma spp., and other genera of the tribe Triatomini. We also present a comparative summary of biology, ecology and epidemiological significance for each species in the genus. This reveals that knowledge of many species is fragmentary or lacking. This is mainly due to the fact that, except for few species with synanthropic traits (P. megistus and P. lignarius [formerly P. herreri]), important vectors of Chagas disease in Brazil and Peru, the majority are sylvatic species, associated with a wide variety of habitats and wild animals (many of them reservoirs of Trypanosoma cruzi). However, trends to invade human dwellings and to establish domestic colonies have been observed in several species in the genus (P. geniculatus, P. rufotuberculatus, P. lutzi, P. chinai), while others are opportunistic species (e.g. P. lignarius in the Amazon basin flying from wild ecotopes to houses on occasion without colonizing). Nevertheless, they can play some role in the transmission of sylvatic T. cruzi to humans. Research on the genus Panstrongylus requires some focus on investigating the natural ecology of these species. This knowledge would add to our understanding of their evolutionary potential and may assist in predicting new epidemiological scenarios, for which new control strategies need to be devised.

Biogeography of Brazilian populations of Panstrongylus megistus (Hemiptera, Reduviidae, Triatominae) based on molecular marker and paleo-vegetational data.

In epidemiological terms, Panstrongylus megistus is one of the most important species of triatomine bug in Brazil. Samples from 11 localities were studied using the random amplification of polymorphic DNA (RAPD) technique, which was able to differentiate the study populations clearly. Biogeographical data indicate that these populations could already have arisen 18,000 years ago (C(14)), it being possible to differentiate insects from the Brazilian states of Santa Catarina (SC) in the south, Ceará (CE) in the northeast and another large intermediate block containing the remaining eight populations from five other states. These results agree with those obtained by phenograms constructed from RAPD data, in which the SC population lies opposite those of CE, consistent with the greatest geographical distance between these localities. The other eight populations (Alagoas (AL), Bahia (BA), Goiás (GO), Minas Gerais (MG) and São Paulo (SP)) are closer genetically and originated in areas whose vegetational characteristics have remained similar to each other during the last 18,000 years, thus allowing greater contact between them. The greatest divergence of this group of insects and those of Ceará appears to have occurred 8000 years ago. This more humid period gave rise to other landscape changes, allowing greater differentiation of the vegetation and consequent expansion of P. megistus populations. Formation of the Serras do Mar and Mantiqueira probably created geographical barriers that favored a certain degree of isolation and greater differentiation of the SC population. Atlantic forest remnants within the caatinga domain (created between 25 and 17,000 years ago), where the CE populations originated probably constitute ecological refugia produced by successive amplification and retraction of the most suitable habitats for this species.

Occurrence and variability of Panstrongylus lutzi in the State of Ceará, Brazil

O Panstrongylus lutzi é um triatomíneo de ocorrência restrita às áreas de "caatinga" do Nordeste brasileiro. Apesar da presença de adultos no ambiente artificial ser freqüente, a ocorrência de colônias nunca havia sido assinalada pelas estatísticas do Programa de Controle da Doença de Chagas. No Estado do Ceará, a ocorrência desta espécie aumentou paulatinamente ao longo do período estudado, com taxas de infecção natural com Trypanosoma cruzi geralmente altas, sempre associadas a adultos que invadem o ambiente artificial. Chama a atenção o encontro de ninfas no peridomicílio e no intradomicílio. No ambiente silvestre duas fêmeas foram coletadas em troncos de árvores, que podem representar ecótopos naturais alternativos para a espécie neste Estado. As amostras de Panstrongylus lutzi dos municípios de Sobral e Crateús estudadas morfológica e morfometricamente, demonstraram alta variabilidade, sendo os insetos de Crateús significativamente menores e de coloração pálida, apresentando alguns indivíduos padrão da morfologia do falo compatível com a descrição da espécie; os insetos de Sobral eram escuros e as genitálias coincidentes com o padrão de Panstrongylus sherlocki, mas sendo todos considerados por nós como Panstrongylus lutzi.

Occurrence and variability of Panstrongylus lutzi in the State of Ceará, Brazil.

Panstrongylus lutzi is generally restricted to the "caatinga" areas of north-eastern Brazil. Adult insects are frequently found in local houses, but colonies have not previously been registered in the statistics of the Control Programme of Chagas Disease. In Ceará State, our study revealed increasing occurrence of this species, usually with high infection rates for Trypanosoma cruzi, and always represented by adults that invaded the artificial environment. We also found nymphs in the peridomicile and inside the houses. In silvatic habitats we collected two adult females from hollow tree trunks, which may represent an alternative natural ecotope for the species in this state. Panstrongylus lutzi entomological collections from Sobral and Crateús, studied by morphology and morphometrics, showed great variability; those from Crateús were larger smaller and paler in colour, with individuals showing genital features consistent with those described for Panstrongylus lutzi or Panstrongylus sherlocki, whereas those from Sobral were darker and with genitalia compatible with P. sherlocki, nevertheless, all were considered to be Panstrongylus lutzi.

Interpopulation variability among Panstrongylus megistus (Hemiptera: Reduviidae) from Brazil.

Comparisons were made among Panstrongylus megistus (Burmeister) from three areas of Brazil (Bahia, Minas Gerais, and Santa Catarina), where populations differ with regard to their degree of association with human dwellings. The following characters were studied: morphology of the eggs and the male genitalia; morphometry of the head and thorax; isoenzyme profile; enzymatic activity of the alpha-glycerophosphate dehydrogenase (alpha-GPDH); and cytogenetics. In general, differences were observed in the weight, diameter, and length of the egg among Bahia, Minas Gerais, and Santa Catarina populations. Differences were not observed in the architecture of the egg exochorion. The size of the median process of the pygophore of the male genitalia of individuals from Bahia differed from the other two populations. The Minas Gerais population presented the largest number of denticles in the endosome process. The morphometry of the head and thorax differentiated Santa Catarina from the Bahia and Minas Gerais populations. Phosphoglucomutase (EC 5.4.2.2., PGM) was the only enzyme out of 11 that showed polymorphism; the population from Minas Gerais was most polymorphic, whereas the population from Santa Catarina was monomorphic. Study of the alpha-GPDH activity and cytogenetics did not reveal differences among the three populations. Analysis of all the characters studied together with information on these three populations from previous publications allowed a phenogram to be constructed. Two distinct groups were evident, one represented by Santa Catarina and the other by Bahia and Minas Gerais. Considering the greater variability of the Minas Gerais and Bahia populations, we propose the inclusion of these states within the area of origin of P. megistus.

Experimental evidence for a demographic cline in Panstrongylus megistus populations

The population biology of three populations of Panstrongylus megistus was compared to determine possible influence on the behaviour and epidemiological importance of this species. The results demonstrated differences in terms of egg eclosion time, nymphal mortality and development rates, and feeding and defaecation rates. These differences appeared to follow a geographical cline, primarily reflecting different degrees of adaptation to domestic habitats