The use of the plasticizer bis(2-ethylhexyl)phthalate (DEHP) and other plasticizers in the manufacture of plastic products has been restricted due to adverse health outcomes such as obesity, metabolic syndrome, and asthma, for which inflammation has been described to be a driving factor. The emerging alternative plasticizer 1,2-cyclohexanedioic acid diisononyl ester (DINCH) still lacks information regarding its potential effects on the immune system. Here, we investigated the effects of DINCH and its naturally occurring metabolite monoisononylcyclohexane-1,2-dicarboxylic acid ester (MINCH) on the innate immune response. Human THP-1 macrophages were exposed to 10 nM–10 μM DINCH or MINCH for 4 h, 16 h, and 24 h. To decipher the underlying mechanism of action, we applied an untargeted proteomic approach that revealed xenobiotic-induced activation of immune-related pathways such as the nuclear factor κB (NF-κB) signaling pathway. Key drivers were associated with oxidative stress, mitochondrial dysfunction, DNA damage repair, apoptosis, and autophagy. We verified increased reactive oxygen species (ROS) leading to cellular damage, NF-κB activation, and subsequent TNF and IL-1β release, even at low nM concentrations. Taken together, DINCH and MINCH induced cellular stress and pro-inflammatory effects in macrophages, which may lead to adverse health effects.

Fibers are interesting materials alternative to replace conventional fossil-based plastics, as they are bio-based and do not lead to CO2 emissions. Due to their limited ductility, it is difficult to use them to make complex three-dimensional shapes. This problem has already been addressed in previous research studies but the processing conditions used here were never tried before. In this thesis, the incorporation of low molecular plasticizers onto the fibers is investigated to obtain a more ductile fiber-based material. More precisely, Paper and Fiber Research Institute (PFI) refining is used to mechanically treat the fibers and help the sorption of glycerol, urea, polyethyleneglycol (PEG), or polyvinylalcohol (PVA), followed by the formation of sheets from the modified pulp. However, it has been found that only small amounts of plasticizers were retained by this process. The refining itself on the fibers without additives enhanced fibrillation and developed mechanical bonding between the fibers, which resulted in increased strength and ductility. Also, the hot pressed (HP) drying technique was found to yield denser and stronger papers, compared to the non-pressed (HP) drying technique. As a comparison, the incorporation of plasticizers through ultrasonication and its effect on the paper properties were also considered from a previous study within the same research group. It has been found that this mechanical treatment retains more plasticizers than refining but yields different paper properties (especially an increased ductility). All these results suggest that PFI refining should be studied more in-depth by performing at least one process optimization cycle where less dilution takes place. / Fibrer är ett intressant, alternativt material att ersätta konventionella, fossila plaster. Men deras begränsade plasticitet gör det svårt att forma mer avancerade tredimensionella former. Detta problem har man adresserat i tidigare forskning, men bearbetningsförhållandena utvärderade i denna studie har inte testats tidigare. I denna uppsats studeras integrering av små molekylära mjukgörare in i fibrer för att framställa ett mer plastiskt, fiber-baserat material. Mer precist, Papirforskninginstituts (PFI) bearbetning används för att mekaniskt bearbeta fibrerna och underlätta sorption av glycerol, urea, Polyethylenglykol (PEG) och Polyvinylalkohol (PVA) följt av arkning av den bearbeta pappersmassan. Det har visats att i denna process bibehålls endast små mängder av mjukgörare på fibrerna. Dock har den mekaniska bearbetning i säg effekt på fibrerna, då den leder till defibrillering, och förstärker interaktionerna mellan fibrerna vilket leder till ett starkare och segare material. Utöver det, visar studien att värmepressningen (HP) som torktekning ger ett mer homogent resultat gällande arkens kvalitet. Som jämförelse användes en tidigare studie av samma forskargrupp som använt ultraljudsbehandling som medel att inkorporera mjukgörare och hur den behandlingen påverkade arken. Den behandlingen leder till högre retention av mjukgörare vilket leder till andra pappersegenskaper, speciellt högre duktilitet. Dessa studier visar att PFI bearbetningen behöver studeras i mer detalj för att se om det är en lämplig bearbetningsmetod och därför bör minst en till cykel med optimeringar göras för att se om högre halt mjukgörare kan bibehållas.

No description available.

Plasticizers are a commonly used additive used in the polymer industry to make the plastic more pliable by reducing the glass transition temperature, Tg and Young's modulus, Y. As the plasticizer aids in polymer process-ability and making it suitable for applications from industrial cables to sensitive medical equipment, the mechanism of plasticization is not fully understood. There are three theories used to explain plasticization: lubricity theory, gel theory, and free volume theory. The latter is a fundamental concept of polymer science that is used to calculate many polymer properties, but they all do not give a clear picture on plasticization. With molecular dynamics (MD) simulation, a coarse-grained (CG) model - which consist of a simple bead-spring model that generalizes particles as a bead and connects them via a finite spring – is used to explore the impact of plasticizer size throughout the polymer system. The interaction characteristics of the plasticizer is explored by representing the plasticizer molecules as a single bead of varying size. This gives better control on the variability of the mixture and pinpoint the significant contributions to plasticization. A path to understanding the the mechanism of plasticization will give insight in glass formation, and can later be used to find an optimal plasticizer architecture to minimize the migration of the additive by tuning the compatibility. Current results show a decoupling between the Tg and Y of the polymer-additive system. The overall understanding of finite-size effects shows: as additive of increasing size is added, the polymer free volume increases which in-turn would decrease the Y, but Tg is shown to increase because the polymer and additive are not as mobile to reduce caging effect of monomeric units. / Thesis / Master of Applied Science (MASc)

This work is concerned with the production of high performance polymer foams via a benign foaming process. The first goal of this project was to develop a process and the conditions necessary to produce a low density (>80% density reduction) foam from poly(arylene ether sulfone) (PAES). Water and supercritical carbon dioxide (scCO2) were used as the blowing agents in a one-step batch foaming process. Both water and scCO2 plasticize the PAES, allowing for precise control on both the foam morphology and the foam density. To optimize the foaming conditions, both thermogravimetric analysis and differential scanning calorimetery (DSC) were used to determine the solubility and the reduced glass transition temperature (Tg) due to plasticization of the polymer. It was determined that 2 hours was sufficient time to saturate the PAES with water and scCO2 when subjected to a temperature of 220 oC and 10.3 MPa of pressure. Under these conditions, a combination of 7.5% of water and scCO2 were able to diffuse into the PAES specimen, correlating to ~60 oC reduction in the Tg of the PAES. The combination of water and scCO2 produced foam with up to an 80% reduction in density. The compressive properties, tensile modulus, and impact strength of the foam were measured. The relative compressive properties were slightly lower than the commercially available structural foam made of poly(methacrylimide). The second objective of the dissertation was to enhance the compressive properties of the PAES foam, without concern for the foam density. Foam was produced over a range of density, by controlling the cell size, in order to optimize the compressive properties. Carbon nanofibers (CNFs) were also added to the PAES matrix prior to foaming to both induce heterogeneous nucleation, which leads to smaller cell size, and to reinforce the cell walls. Dynamic mechanical thermal analysis (DMTA), on saturated CNF-PAES, was used to determine the reduced Tg due to plasticization and establish the temperature for pressure release during foaming. DMTA proved to be more effective than DSC in establishing quantitative results on the reduction in the Tg. The CNF-PAES foam produced had compressive properties up to 1.5 times the compressive properties of the PAES foam. / Ph. D.

Polyacrylonitrile (PAN) and its copolymers are used in a wide variety of applications ranging from textiles to purification membranes, packaging material and carbon fiber precursors. High performance polyacrylonitrile copolymer fiber is the most dominant precursor for carbon fibers. Synthesis of very high molecular weight poly(acrylonitrile-co-methyl acrylate) copolymers with weight average molecular weights of at least 1.7 million g/mole were synthesized on a laboratory scale using low temperature, emulsion copolymerization in a closed pressure reactor. Single filaments were spun via hybrid dry-jet gel solution spinning. These very high molecular weight copolymers produced precursor fibers with tensile strengths averaging 954 MPa with an elastic modulus of 15.9 GPa (N = 296). The small filament diameters were approximately 5 'm. Results indicated that the low filament diameter that was achieved with a high draw ratio, combined with the hybrid dry-jet gel spinning process lead to an exponential enhancement of the tensile properties of these fibers. Carbon fibers for polymer matrix composites are currently derived from polyacrylonitrile copolymer fiber precursors where solution spinning accounts for ~40 % of the total fiber production cost. To expand carbon fiber applications into the automotive industry, the cost of the carbon fiber needs to be reduced from $8 to ~$3-5. In order to develop an alternative melt processing route several benign plasticizers have been investigated. A low temperature, persulfate-metabisulfite initiated emulsion copolymerization was developed to synthesize poly(acrylonitrile-co-methyl acrylate) copolymers with acrylonitrile contents between 91-96 wt% with a molecular weight range of 100-200 kg/mol. This method was designed for a potential industrial scale up. Furthermore, water was investigated as a potential melting point depressant for these copolymers. Twenty-five wt% water lead to a decrease in the Tm of a 93/7 wt/wt % poly(acrylonitrile-co-methyl acrylate) of Mw = 200 kg/mol to 160 0C as measured via DSC. Glycerin, ethylene glycol and glycerin/water combinations were investigated as potential plasticizers for high molecular weight (~200,000 g/mol), high acrylonitrile (93-96 mole:mole %) content poly(acrylonitrile–co-methyl acrylate) statistical copolymers. Pure glycerin (25 wt %) induced crystallization followed by a reduced "Tm" of about 213 °C via DSC. However this composition did not melt process well. A lower MW (~35 kg/mol) copolymer did extrude with no apparent degradation. Our hypothesis is that the hydroxyl groups in glycerin (or water) disrupt the strong dipole-dipole interactions between the chains enabling the copolymer endothermic transition (Tm) to be reduced and enable melting before the onset of degradation. Additionally high molecular weight (Mw = 200-230 kg/mol) poly(acrylonitrile–co-methyl acrylate) copolymers with lower acrylonitrile content (82-85 wt %) were synthesized via emulsion copolymerization and successfully melt pressed. These materials will be further investigated for their utility in packaging applications. / Ph. D.

Master of Science / Department of Grain Science and Industry / Xiuzhi Susan Sun / Soybean oil-based resin for transparent flexible coating applications were formulated by dihydroxyl soybean oil (DSO) with commercial epoxy monomers (i.e., epoxidized soybean oil (ESO) and 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (ECHM)). The resin was formed to thermoset polymers using cationic ring-opening photopolymerization. The ether crosslinking and post-polymerization of the polymeric network were observed using Fourier transform infrared spectroscopy. Thermal properties of the bio-based coating materials and their copolymerization behaviors were examined using a differential scanning calorimetry and a thermogravimetric analyzer. Crosslink density and molecular weight between crosslink were obtained from dynamic mechanical analysis. ECHM/DSO (1: 1.43 weight ratio) films showed the highest elongation at break (49.2 %) with a tensile strength of 13.7 MPa. After 2 months storage, the elongation at break and tensile strength of films were 32 % and 15.1 MPa, respectively. ESO/DSO films (w/w ratios of 1:0.1, 1:0.15, and 1:0.2) exhibited stable flexibility around 11-13 % of elongations at break without significant reductions of tensile strengths (2.5 to 4.4 MPa) during 2-months shelf life. Optical transparencies of the films were comparable to commercial glass and polymers, and water uptake properties (0.72 and 2.83%) were significantly low.

L’un des défis majeurs dans le domaine des polymères est la substitution des molécules pétro-sourcées en vue de l’élaboration de monomères, polymères et d'additifs pour polymères. Le travail de cette thèse s’axe sur la valorisation de molécules bio-sourcées et plus particulièrement, du cardanol et de dérivés d'huiles végétales. Le champ d’application des polymères étant large, nous avons choisi de nous centrer sur trois grandes problématiques.Dans un premier temps, nous nous sommes intéressés à la plastification du PVC qui, actuellement, est majoritairement réalisée par des phtalates, famille d’esters pétro-sourcés vivement suspectés d’être des perturbateurs endocriniens. Des additifs de substitution ont ainsi été synthétisés par une chimie simple à partir du cardanol et d’esters gras. Des stabilités thermiques et des propriétés plastifiantes très satisfaisantes ont été obtenues. Enfin, des tests de toxicité et d’écotoxicité ont démontré l’absence d'impact perturbateur sur la sécrétion d'hormones sexuelles et la non toxicité vis-à-vis de l'environnement de ces plastifiants bio-sourcés.Dans un second temps, nous avons revisité la chimie des résines phénoplastes habituellement préparées à partir du phénol et du formaldéhyde, deux molécules classées CMR. Nous avons adapté cette chimie robuste à un phénol bio-sourcé, le cardanol, et à un aldéhyde bio-sourcé, le nonanal, pour obtenir des résines phénoliques souples. Cette propriété recherchée est le résultat d’une plastification interne des chaines lipidiques pendantes au sein du réseau polymère. Par cet exemple, l’intérêt des dérivés d’huiles végétales pour l’élaboration de matériaux souples a été démontré. Un compromis entre la souplesse des résines phénoliques et leurs résistances chimique et thermique a été atteint.Enfin, nous nous sommes tournés vers l’élaboration de polyuréthanes réticulés à partir d’un ester gras, d’un diester gras et d’un triglycéride porteurs de fonctions alpha-hydroxycétone (collaboration avec l’équipe CASYEN de l’ICBMS). L’apport de la fonction alpha-cétone sur la réactivité du polyol vis-à-vis du réactif isocyanate n’est que modeste par rapport à des dérivés présentant un groupement alcool isolé sur la chaine (huile de ricin) et alcool associé à une autre fonction alcool (triglycéride 1,2-diol). Néanmoins, la présence d’interactions intramoléculaires provenant des groupements cétone a permis d’exacerber la stabilité thermique des matériaux PU et d’élaborer des PU réticulés souples par plastification interne comme dans le cas des résines phénoliques.Cette thèse a ainsi démontré l’apport des phénols lipidiques tels que le cardanol et des chaines grasses dans l’amélioration de la stabilité thermique et de la souplesse au sein de matériaux polymères. / One of the major challenges in the field of polymers is the substitution of oil-based molecules for the development of monomers, polymers and polymer additives. The topic of this thesis is focused on the valorization of bio-sourced molecules and particularly, cardanol and vegetable oil derivatives. Since the scope of polymers is broad, we have chosen to focus on the following three major issues.At first, we were interested in the plasticization of PVC, which is most often carried out by phthalates, a family of oil-based esters strongly suspected to be endocrine disruptors. Alternative additives were thus synthesized by simple chemical reactions from cardanol and fatty esters. Good thermal stabilities and satisfactory plasticizing properties were obtained. Finally, toxicity and ecotoxicity tests have demonstrated the absence of a disruptive impact on the secretion of sex hormones and the non-toxicity towards the environment of these bio-sourced plasticizers.In a second step, we were interested in the chemistry of phenolic resins usually prepared from phenol and formaldehyde, two molecules classified as CMR substances. Thus, a bio-sourced phenol, cardanol, and a bio-sourced aldehyde, nonanal, were reacted to reach flexible phenolic resins. This peculiar property is the result of internal plasticization of the pendant lipid chains within the polymer network. By this example, the interest of vegetable oil derivatives for the production of flexible materials was demonstrated. Finally, a compromise between the flexibility of phenolic resins and their chemical and thermal resistances was reached.Finally, we turned to the development of crosslinked polyurethanes from a fatty ester, a fatty diester and a triglyceride exhibiting alpha-hydroxyketone functions (collaboration with the CASYEN team of the ICBMS). The contribution of the alpha-ketone function on the reactivity of the related to the isocyanate reagent is only modest compared to isolated alcohol type derivatives (castor oil) and alcohol associated with another alcohol function ( triglyceride 1,2-diol). Nevertheless, the presence of intramolecular interactions from ketone groups made possible to enhance the thermal stability of the PU materials and to develop flexible crosslinked PUs by internal plasticization, as in the case of phenolic resins.This thesis brings out the advantages provided by the use of lipid phenols such as cardanol and fatty chains for the improvement of thermal stability and flexibility of polymer materials.

<p>This thesis studied environmental factors in relation to asthma and respiratory symptoms among schoolchildren in two countries. In Sweden, 1014 pupils (5-14 year) in 8 schools participated. Wheeze was reported by 7.8%, current asthma by 5.9%, doctor-diagnosed asthma by 7.7%, cat allergy by 6.8% and dog allergy by 4.8%. Current asthma was less common among those consuming more fresh milk and fish. Doctor-diagnosed asthma was less common among those consuming olive oil. Cat, dog and horse allergens were common in settled dust and related to respiratory symptoms. Pupils consuming butter and fresh milk had less respiratory symptoms in relation to allergen exposure. In schools with increased levels of microbial volatile organic compounds and selected plasticizers (Texanol and TXIB) asthma and respiratory symptoms were more common.</p><p>In Korea, 2365 pupils (9-11 year) in 12 schools participated (96%). In total, wheeze was reported by 8.0%, current asthma by 5.7%, doctor-diagnosed asthma by 5.4%, cat allergy by 2.6% and dog allergy by 4.9%. Contamination of dog and mite (<i>Dermatophagoides farinae</i>) allergen was common while cat allergen was uncommon. Remodelling, changing floor and building dampness at home were positively associated with asthma and respiratory symptoms. The strongest associations were found for floor dampness. Indoor/outdoor concentration of NO₂, formaldehyde and ultrafine particles (UFP) at schools were positively associated with asthma and respiratory symptoms. </p><p>When comparing Sweden and Korea, Korean pupils had more breathlessness and asthma but reported less cat and pollen allergy. Swedish schools had CO₂-levels below 1000 ppm, while most Korean schools exceeded this standard. Since both home and school environment may affect pupil’s asthma and respiratory symptoms, air quality should be an important health issue. Moreover, changes in dietary habits may be beneficial to decrease asthma and allergies. Furthermore, interaction between diet and environment needs to be further investigated.</p>

This thesis studied environmental factors in relation to asthma and respiratory symptoms among schoolchildren in two countries. In Sweden, 1014 pupils (5-14 year) in 8 schools participated. Wheeze was reported by 7.8%, current asthma by 5.9%, doctor-diagnosed asthma by 7.7%, cat allergy by 6.8% and dog allergy by 4.8%. Current asthma was less common among those consuming more fresh milk and fish. Doctor-diagnosed asthma was less common among those consuming olive oil. Cat, dog and horse allergens were common in settled dust and related to respiratory symptoms. Pupils consuming butter and fresh milk had less respiratory symptoms in relation to allergen exposure. In schools with increased levels of microbial volatile organic compounds and selected plasticizers (Texanol and TXIB) asthma and respiratory symptoms were more common. In Korea, 2365 pupils (9-11 year) in 12 schools participated (96%). In total, wheeze was reported by 8.0%, current asthma by 5.7%, doctor-diagnosed asthma by 5.4%, cat allergy by 2.6% and dog allergy by 4.9%. Contamination of dog and mite (Dermatophagoides farinae) allergen was common while cat allergen was uncommon. Remodelling, changing floor and building dampness at home were positively associated with asthma and respiratory symptoms. The strongest associations were found for floor dampness. Indoor/outdoor concentration of NO2, formaldehyde and ultrafine particles (UFP) at schools were positively associated with asthma and respiratory symptoms. When comparing Sweden and Korea, Korean pupils had more breathlessness and asthma but reported less cat and pollen allergy. Swedish schools had CO2-levels below 1000 ppm, while most Korean schools exceeded this standard. Since both home and school environment may affect pupil’s asthma and respiratory symptoms, air quality should be an important health issue. Moreover, changes in dietary habits may be beneficial to decrease asthma and allergies. Furthermore, interaction between diet and environment needs to be further investigated.