Abstract. A series of hybrids composed of styrene crosslinkable vinyl ester (VE) and acrylated epoxidized soybean oil (AESO) were produced via free radical-induced crosslinking. The VE/AESO ratio was changed between 75/25 and 25/75 wt%. Moreover, to support phase grafting the VE/AESO = 50/50 wt% hybrid was modified with phthalic anhydride in various amounts (1, 5 and 10 wt%). The structure of the hybrid systems was investigated by dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), and atomic force microscopy (AFM). The properties of the systems were assessed by static flexural and fracture mechanical tests. The resistance to thermal degradation was inspected by thermogravimetric analysis (TGA). The results suggested that the hybrids have an interpenetrating network (IPN) structure. With increasing AESO content the stiffness (modulus), strength and glass transition temperature (Tg) of the hybrids decreased, whereas their ductility increased. Phthalic anhydride caused an adverse trend. Both the fracture toughness and fracture energy increased with increasing AESO content. They were less affected by adding phthalic anhydride phase couplant. Interestingly, the hybrids outperformed the parent VE and AESO in respect to resistance to thermal degradation.

No description available.

Doctor of Philosophy / Department of Grain Science and Industry / Xiuzhi Susan Sun / Renewable materials are desirable for many applications due to the finite fossil resources and environmental issues. Plant oil is one of the most promising renewable feedstocks. Plant oils and functionalized oleo-chemicals including functionalized soybean oils have become attractive sustainable chemicals for industrial applications. Especially, epoxidized oleo-chemicals such as epoxidized soybean oil (ESO) are one of the most well-known readily available inexpensive functionalized plant oils. In this study, novel polymers and nanocomposites for sustainable materials applications were designed and prepared via ring-opening of epoxide in plant oils, and their chemical and physical properties were characterized. The novel transparent elastomers derived from functionalized plant oils have a great potential as flexible electronic and biological applications with their inherent low toxicity. Especially, their rheological properties showed a potential for pressure sensitive adhesives (PSAs). The dominant thermal stability and transparency were obtained via green processing: one pot, single step, fast reactions in moderate conditions, or solvent-free UV curing conditions. These oleo-based elastomers presented excellent end-use properties for PSAs application comparable to commercial PSA tapes. Based on the principal chemical studies, the roles of the each component have been identified: polymer derived from the ring-opening of epoxides as an elastomer, and dihydroxylated triglycerides as a tackifier. Their interaction was also elucidated with an element label analysis. The mechanical and rheological properties of the oleo-polymer as PSAs were able to be improved with a rosin ester tackifier. In addition, biogreases and bio-thermoplastics were developed via the environmentally benign process, which will contribute to further application on the production of new bio-based materials. Further, this study essays a novel acid functionalized iron/iron oxide nanoparticles catalyst with excellent product yields for epoxide ring opening of oleochemicals for a greener synthetic method of biopolyols, and excellent environmental benefits with life cycle assessment of syntheses. Those functionalized iron/iron oxide core shell nanoparticles catalysts has great potential for biomedical engineering process with the highest magnetization of Fe(0) core among all metals.

Améliorer le recyclage des caoutchoucs est un enjeu majeur de la société actuelle. Ces matériaux sont classiquement réticulés de manière permanente par chimie covalente, ce qui empêche toute modification ultérieure de la structure du réseau. Au cours de cette thèse, nous avons cherché à concevoir le recyclage en amont, en utilisant des méthodes de réticulation non-permanentes. Le caoutchouc naturel époxydé (ENR), choisi comme élastomère de base de l'étude, est efficacement réticulé par l'action de diacides carboxyliques qui réagissent sur les fonctions oxiranes pour former des ponts esters. D'une part, l'ajout d'un catalyseur de transestérification au sein du matériau a permis d'envisager l'obtention de propriétés vitrimères. Les avantages de cette chimie covalente échangeable sont mis en évidence par comparaison avec les réseaux permanents faiblement réticulés qui montrent eux aussi des propriétés de relaxation et d'adhésion. D'autre part, l'utilisation d'un diacide comportant dans sa chaîne une fonction disulfure dynamique apporte un certain degré de recyclabilité, comparable à ce qui peut être obtenu par vulcanisation conventionnelle au soufre. La chimie décrite ici présente cependant l'avantage majeur de ne pas être toxique pour l'environnement, contrairement à la vulcanisation. Enfin, le greffage d'acides gras à chaîne cristallisable sur l'ENR conduit à l'obtention d'élastomères thermoplastiques. L'étude par diffraction des rayons-X sous traction cyclique montre que ces réseaux physiques cristallisent sous contrainte aussi bien que l'ENR réticulé chimiquement aux diacides. / Improving rubber recyclability is a major challenge of today’s society. These materials are usually crosslinked through permanent covalent chemistry, which prevents any further modification of the network structure. The aim of this thesis was to design the recyclability up-stream by using non-permanent chemistry for rubber crosslinking. Epoxidized natural rubber (ENR), chosen as the base rubber, is efficiently crosslinked by reaction of dicarboxylic acids on oxirane rings to form ester bonds. On the one hand, the addition of a transesterification catalyst let foresee the obtaining of vitrimer properties. The advantages of this exchangeable chemistry are shown by comparison to lightly permanently crosslinked rubbers that also show stress relaxation and adhesion properties. On the other hand, using a functionalized diacid with a central disulphide function, a certain degree of reprocessability could be obtained, comparable to what was obtained by conventional sulphur vulcanization. A major advantage of the presented diacid chemistry over vulcanization is the non-toxicity towards the environment. Lastly, by grafting long crystallizable fatty acids onto ENR, we synthesized thermoplastic elastomers. Like diacid-crosslinked ENR (chemical network), these physical networks show strain-induced crystallization measured by X-ray diffraction during cyclic tensile tests.

<p>Adhesives  are  found  in  almost  every  aspect  of  the  modern  world.  They  are  found  in plywood used in buildings, electronics, shoes, plumbing and in almost every facet of your daily life. Nature also has an abundance of these adhesives that are used fora multitude of applications. Some  animals, like  the  blue  mussel, use  their  adhesive  for  protection  against  ocean  waves  and predators  while other animals, such  as  the  spider, use  it  to  trap  prey. Investigation  of  theses adhesives has led to the identification of several different proteins that allow for these animals to make  their  adhesive.  Some  of  them  are  composed of rare  amino  acids that  while  other  animals use  a combination  of  inorganic  and  organic  components.  Understanding  of  these  unique adhesives  can be  a  boon  for designof future  adhesives  that  do  not  have  the disadvantagesof current day commercialized glues.</p> <p>Increasing interest  in  the  restoration  of  natural  oyster  reefs  and  the  cement  that  holds them  together  has  resulted  in  the  identification  of  the  Shelk2  protein  that  is  found  both  in  the mantle  of  the  oyster’s  shell  as  well  as  the  cement  that  holds  the  reefs  together. Gaining  an understanding  of  how  this  protein  functions  and  its  part  in  the  oyster  reef  could  be  quite beneficial  for  projects  investing  in  reef  restorations  as  well  as  underwater  adhesion.  Gathering protein  from  the  animal  for  experimentation  and  characterization  can  be  labor  intensive  and extremely challenging. Luckily, cloning technology has become a useful tool for the expression of large quantities of proteins that can be difficult or impossible to gather from the native animal. Using <em>E. coli</em>, it  is  possible  to design  and express  this protein  in  hopes  of  gaining  a  better understanding of its impact on oyster settlement and adhesion.</p> <p>Sustainability is a major downside to current day adhesives that current technologies have not  been  able  to  solve. Most adhesives  that  are  on  the  market  today  are  primarily  derived  from petroleum. Current  research  has  begun  investigating  alternatives  to  the  large   epoxy   and formaldehyde  adhesive  market,  but  the  barrier  of  entry  is  hard  to  overcome.  To  replace  these glues  the  new  material  must  be  affordable,  non-petroleum  derived,  and  available  on  a  massive scale.  These  requirements  are  hard  to  meet  for  many  materials  and  due  to  that  the  current  bio-adhesive are generally very low strength.</p> <p>The work presented here will detail the characterization, and expression of some of these natural  adhesives that  have  been  found  in  the  Eastern  oyster. Another  aspect of  this  work includes the synthesis of a new bio-based adhesive system. Utilizing biomimetic chemistry along with  sustainably  sourced  materials  a  new  adhesive  has  been  formulated that  has  comparable adhesive strength to current day commercial adhesives.</p>

Cette thèse présente l’élaboration de thermodurcissables et de composites biosourcés synthétisés à partir d’huiles végétales époxydées (lin et soja) et d’alcool furfurylique (FA). La première partie de ce travail concerne l’étude de la polymérisation du FA en polyalcool furfurylique (PFA) (i) en solvants protiques polaires, (ii) en combinaison avec le bois et (iii) suivant l’ajout de nouveaux amorceurs. En solvant, les changements de structures observés ont été reliés aux propriétés thermomécaniques. Une autre modification de structure du PFA a été obtenue grâce au 2,5 diméthylfurane. Ce travail a permis d’obtenir une meilleure compréhension de la réactivité du FA au sein du bois et montre que les composites bois/PFA ont une densité et une résistance plus élevées que leurs homologues non modifiés. Enfin, l’amorçage des réactions du FA par l’acide lévulinique ou par le p-toluène sulfonylhydrazine permet de proposer deux nouveaux amorceurs, respectivement biosourcé et « latent ». La seconde partie de ce travail concerne l’élaboration d’une résine époxyde totalement biosourcée et synthétisée à partir d’huiles végétales époxydées. L’huile de lin et de soja ont été chacune copolymérisées avec un acide dicarboxylique. Un premier travail fondamental a consisté à corréler la réactivité de copolymérisation avec les structures des polymères obtenus puis à établir le lien avec les propriétés thermomécaniques. Ensuite, des nanocomposites ont été synthétisés à partir de ces résines époxydes et de sépiolite. Les différentes voies de dispersion et de modification de la sépiolite mises en œuvre conduisent à des niveaux de dispersion différents de la nanocharge au sein de la matrice. / The work presents the elaboration of biobased thermosets and composites synthesized from epoxidized vegetable oils (linseed and soybean) and furfuryl alcohol (FA). A first area of research focused on the study of the polymerisation of FA into polyfurfuryl alcohol (PFA) (i) in protic polar solvents, (ii) in combination with wood and (iii) in the presence of new reaction initiators. In presence of solvents, the observed structural changes have been linked to the thermomechanical properties. Another PFA structure modification was obtained with 2,5 dimethylfuran. This work allowed a better understanding of the reactivity of FA within the wood and shows that the obtained wood/PFA composites have higher density and resistance than their non-modified equivalents. Finally, the initiation of FA polymerization by levulinic acid and p-toluene sulfonylhydrazine, respectively biobased and « latent » initiators has been studied. The second topic of thesis concerns a new type of fully bio-based epoxy resin synthesized from epoxidized vegetable oils. Linseed and soybean oils have both been copolymerized with a dicarboxylic acid as curing agent. A first fundamental work was to correlate the reactivity of copolymerization with the polymer structure and to link them with thermomechanical properties. The obtained thermosets have been used to prepare nanocomposites with sepiolite. Different methods of dispersion and/or modification of sepiolite conduct to diverse morphologies of nanofiller dispersions into the matrix.

A demanda pelo uso de formulações biodegradáveis e provenientes de fontes renováveis tem motivado o desenvolvimento de biofluidos de resfriamento para aplicação em têmpera de aços. Os óleos vegetais são potenciais candidatos a serem empregados como base destas formulações, porém, a baixa estabilidade termo-oxidativa inibe sua maior utilização pela indústria. As modificações químicas na cadeia carbônica dos óleos vegetais podem promover melhoria nesta característica, sendo epoxidação uma das mais comuns. O presente trabalho estudou, primeiramente, a estabilidade termo-oxidativa de formulações contendo óleo de soja epoxidado (ESBO) e éster metílico de ácido graxo (FAME), em diferentes concentrações, por Calorimetria Exploratória Diferencial com Pressão (PDSC). Posteriormente, o desempenho destes biofluidos, no tratamento térmico de têmpera, foi avaliado pela análise microestrutural e medições de dureza (curvas em U) nos aços SAE 1045 e SAE 4140, comparando-o com o desempenho promovido pelos fluidos derivados de petróleo. As tensões térmicas residuais foram simuladas com o ABAQUS, usando os coeficientes de transferência de calor obtidos pela solução do problema inverso. As distorções causadas pelos biofluidos foram estudadas em corpos Navy-C-rings modificados de aço SAE 4140. Além disto, a viscosidade dos biofluidos também foi estudada em função da temperatura por estar diretamente relacionada à propriedade de molhamento, que influencia a transferência de calor durante o processo de resfriamento. A adição de FAME no ESBO foi eficiente na redução da viscosidade das formulações propostas, em função da temperatura, adequando-as para utilização como fluidos de resfriamento. As formulações EF30 e EF38 apresentaram temperatura inicial de oxidação (OOT) superior ao óleo de soja, indicando assim, maior estabilidade termo-oxidativa. Todas bioformulações foram eficientes na têmpera de ambos os aços, nos diâmetros ensaiados, promovendo dureza mínima de aproximadamente 52 HRC no centro dos corpos SAE 4140, dureza esta, comparável àquela promovida pelos fluidos minerais. Comportamento similar foi observado para o aço de menor temperabilidade. As tensões térmicas residuais simuladas não variam em magnitude em função da composição das formulações, enquanto que as distorções tenderam a aumentar em função do aumento do FAME nas formulações. / The search for biodegradable and renewable basestocks has motivated the development of bioquenchants for steel heat treatment. Vegetable oils are potential candidates, however, their poor thermo-oxidative stability inhibits a wide industrial application. Modifications of the chemical structure of vegetable oils may be used to improve this characteristic and epoxidation is one of the most common approaches reported to date. The first step of the study reported here was to analyze and compare the thermo-oxidative stability of soybean oil, epoxidized soybean oil (ESBO) and different blend ratios of ESBO with a soybean oil-derived fatty acid methyl ester (FAME) by Pressure Differential Scanning Calorimetry (PDSC). Subsequently, the quenching performance of the formulations was evaluated by cooling curve analysis and microstructural analysis and hardness measurements by U-curves analysis of SAE 1045 and SAE 4140 steels and then, compared with results obtained using commercially available petroleum oil quenchants. Thermal residual stress profiles were simulated with ABAQUS, using the heat transfer coefficients obtained by an inverse method. Bioquenchant distortions were determined using SAE 4140 steel and a so-called modified Navy C-ring test. Moreover, the viscosity-temperature property of bioquenchants was also studied, since it is directly related to the heat transfer and wetting behavior occurring during the cooling process. Although the viscosity of ESBO was too high for use as a quenchant, increasing FAME addition to ESBO provided sufficient reduction of resulting kinematic viscosities to permit their potential use as quenchants. EF30 and EF38 (30% and 38% FAME, respectively) exhibited onset oxidation temperatures (OOT) higher than soybean oil, thus indicating better thermo-oxidative stability. All bioquenchants were effective for both steels, at the specimen diameters tested, producing a minimum hardness of approximately 52 HRC at the center of the SAE 4140 test specimen. This hardness is comparable to that obtained with the petroleum-based fluids. Comparable results were obtained for the lower hardenability SAE 1045 steel. The simulated residual stress profiles did not vary in terms of magnitude as a function of formulation composition while the distortions tended to increase as FAME is added in the formulations.

Cationic photopolymerization of multifunctional epoxides is very useful for efficient cure at room temperature and has been widely used in coatings and adhesives. Despite excellent properties of the final cured polymers, cationic photopolymerizations of epoxides have seen limited application due to slow reactions (relative to acrylates) and brittleness associated with a highly crosslinked, rigid network. To address these issues, two reaction systems were studied in this thesis: photoinitiated cationic copolymerizations of a cycloaliphatic diepoxide with epoxidized elastomers and acrylate/epoxide hybrid photopolymerizations. Oligomer/monomer structures, viscosity, compositions, and photoinitiator system were hypothesized to play important roles in controlling photopolymerizations of the epoxide-based mixtures. A fundamental understanding of the interplay between these variables for the chosen systems will provide comprehensive guidelines for the future development of photopolymerization systems comparable to the epoxide-based mixtures in this research. For diepoxide/oligomer mixtures, the observed overall enhancement in polymerization rate and ultimate conversion of the cycloaliphatic diepoxide was attributed to the activated monomer mechanism associated with hydroxyl terminal groups in the epoxidized oligomers. This enhancement increased with increasing oligomer content. The mixture viscosity influenced the initial reactivity of the diepoxide for oligomer content above 50 wt.%. Real-time consumption of internal epoxides in the oligomers was successfully determined using Raman spectroscopy. Initial reactivity and ultimate conversion of the internal epoxides decreased with increasing the diepoxide content. This trend was more pronounced for the oligomer containing low internal epoxide content. These results indicate that the reactivity of the hydroxyl groups is higher toward cationic active centers of the diepoxide than those of the internal epoxides in the oligomers. These conclusions are consistent with physical property results. The enhanced fracture toughness and impact resistance were attributed to multimodal network chain-length distribution of copolymers containing the oligomer content between 70% and 80%. For acrylate/epoxide hybrid mixtures, diacrylate oligomers significantly suppressed reactivities of cycloaliphatic mono/diepoxides, which was attributed to high mixture viscosity and highly crosslinked acrylate network. In this case, the dual photoinitiator system did not favor the epoxide reaction. Depending on the monovinyl acrylate secondary functionalities, enhanced reactivity and ultimate conversion of the diepoxide were attributed to a combined effect of a reduced viscosity and the radical-promoted cationic polymerization associated with the dual photoinitiator. The retarded and inhibited diepoxide reactivities with ether and urethane secondary groups were attributed to solvation and nucleophilicity/basicity effects, respectively. The influence of the diepoxide on the acrylate reactivity was attributed to dilution and polarity effects. In this case, high concentration of the free-radical photoinitiator is required for the dual photoinitiator system. Physical properties of hybrid polymers also varied with acrylate structures and monomer composition. Dynamic modulation methods were proposed to enhance the diepoxide reactivity and final properties in the presence of urethane acrylates.

A demanda pelo uso de formulações biodegradáveis e provenientes de fontes renováveis tem motivado o desenvolvimento de biofluidos de resfriamento para aplicação em têmpera de aços. Os óleos vegetais são potenciais candidatos a serem empregados como base destas formulações, porém, a baixa estabilidade termo-oxidativa inibe sua maior utilização pela indústria. As modificações químicas na cadeia carbônica dos óleos vegetais podem promover melhoria nesta característica, sendo epoxidação uma das mais comuns. O presente trabalho estudou, primeiramente, a estabilidade termo-oxidativa de formulações contendo óleo de soja epoxidado (ESBO) e éster metílico de ácido graxo (FAME), em diferentes concentrações, por Calorimetria Exploratória Diferencial com Pressão (PDSC). Posteriormente, o desempenho destes biofluidos, no tratamento térmico de têmpera, foi avaliado pela análise microestrutural e medições de dureza (curvas em U) nos aços SAE 1045 e SAE 4140, comparando-o com o desempenho promovido pelos fluidos derivados de petróleo. As tensões térmicas residuais foram simuladas com o ABAQUS, usando os coeficientes de transferência de calor obtidos pela solução do problema inverso. As distorções causadas pelos biofluidos foram estudadas em corpos Navy-C-rings modificados de aço SAE 4140. Além disto, a viscosidade dos biofluidos também foi estudada em função da temperatura por estar diretamente relacionada à propriedade de molhamento, que influencia a transferência de calor durante o processo de resfriamento. A adição de FAME no ESBO foi eficiente na redução da viscosidade das formulações propostas, em função da temperatura, adequando-as para utilização como fluidos de resfriamento. As formulações EF30 e EF38 apresentaram temperatura inicial de oxidação (OOT) superior ao óleo de soja, indicando assim, maior estabilidade termo-oxidativa. Todas bioformulações foram eficientes na têmpera de ambos os aços, nos diâmetros ensaiados, promovendo dureza mínima de aproximadamente 52 HRC no centro dos corpos SAE 4140, dureza esta, comparável àquela promovida pelos fluidos minerais. Comportamento similar foi observado para o aço de menor temperabilidade. As tensões térmicas residuais simuladas não variam em magnitude em função da composição das formulações, enquanto que as distorções tenderam a aumentar em função do aumento do FAME nas formulações. / The search for biodegradable and renewable basestocks has motivated the development of bioquenchants for steel heat treatment. Vegetable oils are potential candidates, however, their poor thermo-oxidative stability inhibits a wide industrial application. Modifications of the chemical structure of vegetable oils may be used to improve this characteristic and epoxidation is one of the most common approaches reported to date. The first step of the study reported here was to analyze and compare the thermo-oxidative stability of soybean oil, epoxidized soybean oil (ESBO) and different blend ratios of ESBO with a soybean oil-derived fatty acid methyl ester (FAME) by Pressure Differential Scanning Calorimetry (PDSC). Subsequently, the quenching performance of the formulations was evaluated by cooling curve analysis and microstructural analysis and hardness measurements by U-curves analysis of SAE 1045 and SAE 4140 steels and then, compared with results obtained using commercially available petroleum oil quenchants. Thermal residual stress profiles were simulated with ABAQUS, using the heat transfer coefficients obtained by an inverse method. Bioquenchant distortions were determined using SAE 4140 steel and a so-called modified Navy C-ring test. Moreover, the viscosity-temperature property of bioquenchants was also studied, since it is directly related to the heat transfer and wetting behavior occurring during the cooling process. Although the viscosity of ESBO was too high for use as a quenchant, increasing FAME addition to ESBO provided sufficient reduction of resulting kinematic viscosities to permit their potential use as quenchants. EF30 and EF38 (30% and 38% FAME, respectively) exhibited onset oxidation temperatures (OOT) higher than soybean oil, thus indicating better thermo-oxidative stability. All bioquenchants were effective for both steels, at the specimen diameters tested, producing a minimum hardness of approximately 52 HRC at the center of the SAE 4140 test specimen. This hardness is comparable to that obtained with the petroleum-based fluids. Comparable results were obtained for the lower hardenability SAE 1045 steel. The simulated residual stress profiles did not vary in terms of magnitude as a function of formulation composition while the distortions tended to increase as FAME is added in the formulations.

L’objectif de ce travail est de préparer des polymères composites antimicrobiens, utilisant de l’acide polylactique (PLA) et/ou du caoutchouc naturel époxydé et incluant des particules d’argent insérées dans des matrices zéolites (AgZ), agissant en tant que composé actif. Un des verrous contrôlant l’activité antibactérienne des matériaux synthétisés est relié à l’étude de l’absorption de l’eau. En effet la mise en œuvre de composites PLA antibactériens rencontre le problème du caractère faiblement hydrophile de PLA, induisant une faible efficacité antimicrobienne. Ainsi afin d’amplifier l’activité antibactérienne des composites AgZ/PLA, une solution prometteuse consiste à introduire un second polymère hautement polaire et flexible. Le caoutchouc naturel époxydé a été ainsi sélectionné pour être associé au composite AgZ/PLA et le taux d’absorption d’eau mesuré témoigne d’un accroissement notable. La morphologie et la distribution des particules AgZ a été étudiée. L’accroissement remarquable du caractère antibactérien des composites ENR/AgZ/PLA a été démontré ; ainsi des tests menés sur S. aureus montrent que la croissance bactérienne a été inhibée à hauteur de 98-99%. L’étude a aussi été menée en fonction de la proportion de caoutchouc et des particules AgZ. De plus les composites ENR/AgZ/PLA possèdent une plus haute résistance à l’impact comparés à l’emploi de PLA pur, suggérant ainsi que ces nouveaux composites pourront constituer des matériaux de choix pour des applications à la fois antibactériennes et nécessitant une résistance à l’impact forte. / The aim of this work is to prepare antibacterial polymers composites, involving especially poly(lactic acid) (PLA) and epoxidized natural rubber (ENR) in the presence of silver-substituted zeolites (AgZ) as an active ingredient. Herein, the key to control the antibacterial activity of the composites which is the water absorption characteristic was thoroughly studied. In general, the fabrication of antibacterial PLA composites encounters with the problem relating to the poor hydrophilicity of PLA which is the cause of antibacterial ineffectiveness. To enhance the antibacterial activity of the composites, blending with the second polymer having high polarity and flexibility is a promising way to produce the antibacterial AgZ/PLA composite. Herein, epoxidized natural rubber (ENR) was selected to blend with AgZ/PLA composites and the increase in the water absorption percentage could be observed. The morphology as well as the AgZ distribution in the composites were also investigated. The remarkable enhancement of antibacterial activity of ENR/AgZ/PLA composites was observed because more than 98-99% inhibition of S. aureus growth was found. Furthermore, the effects of rubber content and amount of AgZ on the antibacterial activity of the composites were investigated. Moreover, the ENR/AgZ/PLA composites possessed the higher impact resistance compared to neat PLA, suggesting that the improved composites might be a choice in applications at which both antibacterial activity and impact resistance property are of great importance.