Physicochemical Properties Of Poly Research Articles

Effect of stabilizer type on the physicochemical properties of poly(acrylic acid)/silver nanocomposites for biomedical applications

Poly(acrylic acid), PAA, has been mixed in solution with silver nanoparticles, obtained by chemical reduction of silver nitrate. Two different sulfur-containing organic compounds have been used as stabilizers of Ag nanoparticles: mercaptosuccinic acid (MSA) and 3-mercaptopropionic acid (MPA). The formation of Ag nanoparticles has been monitored by UV–Vis spectroscopy. The morphology and composition of obtained nanomaterials has been studied by electron microscopy techniques (SEM/EDX and HR-TEM). Nanomechanical properties of nanocomposites (adhesion and nanohardness) have been investigated by Atomic Force Microscopy (AFM). Thermal stability has been determined using thermogravimetric analysis. The exposure of specimens to UV radiation allowed to observe the changes in the nanoparticle structure and to estimate nanocomposite photostability. MSA has proved to be a better stabilizer of Ag nanoparticles immediately after the synthesis, when MPA provides better storage stability. MPA has allowed for the creation of nanoparticles using mixed reduction (chemical/photochemical) of AgNO3. It has been found that the nanocomposite materials are stable for 12 months of storage in solution and in solid form.

Synthesis and Physico-Chemical Properties of Poly(methylmethacrylate)-Modified Silica Aerogels by Ambient Pressure Drying

Synthesis and Physico-Chemical Properties of Poly(methylmethacrylate)-Modified Silica Aerogels by Ambient Pressure Drying

Surface modification of poly(dimethylsiloxane) through oxygen and nitrogen plasma treatment to improve its characteristics towards biomedical applications

Polymeric materials successfully applied in biomedical applications have an issue of poor surface properties which may restrict their applications as biomaterials. The present paper aims to study the effect of oxygen and nitrogen plasma treatment on physico-chemical properties of poly(dimethylsiloxane) (PDMS) and enhancement in its biocompatibility. Various characterization techniques including Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, scanning electron microscopy (SEM), atomic force microscopy were used to evaluate the changes in surface chemistry and morphology of plasma treated PDMS. Changes in the wettability after plasma treatments and the effects of ageing on wettability were studied by contact angle measurement. Ageing studies showed that the contact angle was stable after two hours. The effect of plasma treatment on biocompatibility was studied through cell adhesion and MTT using 3T3 fibroblast cells. Morphology of cells obtained through SEM was analyzed using ImageJ software. Among the different treated and untreated samples, substantial enhancement in biocompatibility was observed for nitrogen plasma treated PDMS for 5 min in terms of highest cell area observed from cell adhesion test and highest cell viability observed from MTT test. This may be probably due to its highest polarity (0.4) and surface energy (33.3 N mm−2) with a moderate surface roughness (Rrms = 100.24 nm) among the other treated and untreated samples.

Effect of ionic liquid anion and cation on the physico-chemical properties of poly(vinylidene fluoride)/ionic liquid blends

Poly(vinylidene fluoride), PVDF, has been blended with different ionic liquids (IL) in order to evaluate the effect of the different IL anions and cations on the electroactive β-phase, thermal, mechanical and electrical properties of the polymer blend. [C2MIM][Cl], [C6MIM][Cl], [C10MIM][Cl], [C2MIM][NTf2], [C6MIM][NTf2], [C10MIM][NTf2] have been selected and were introduced in the polymer at a weight percentage of 40wt%. It was found that the incorporation of ILs into the PVDF matrix leads to an increase of the β-phase content due to the strong electrostatic interactions between the dipolar moments of PVDF and the ILs. Further, the incorporation of ILs into PVDF strongly decreases the elastic modulus and increases the electrical conductivity of the blend with respect to the pure polymer matrix, all these effects being accompanied by a modification of the crystallization kinetics, as indicated by the modified spherulitic microstructure. Thus, novel PVDF/IL blends films with high transparency, excellent antistatic properties, and highly polar crystal form fraction were successfully achieved.

Novel poly(N-vinyl-2-pyrrolidone) nanocomposites containing poly(amide–imide)/aluminum oxide nanostructure hybrid as a filler

In this work, the physicochemical properties of poly( N-vinyl-2-pyrrolidone) (PVP) reinforced with the poly(amide–imide)/alumina nanocomposite (PAN) under sonochemical treatment were studied. In the process of manufacturing PAN, the surface of alumina nanoparticles was grafted with 15 wt% of the bioactive dicarboxylic acid based on amino acid, and an amount of 10 wt% of this modified nanoparticle was loaded into the poly(amide–imide) using some powerful ultrasound irradiation. Subsequently, in order to prepare the PVP-PAN, various contents (2, 4, and 6 wt%) of the PANs were incorporated into the PVP matrix. The structure morphology and the physical properties of the obtained PVP/PANs were analyzed by Fourier transform infrared spectroscopy, X-ray diffraction, thermal gravimetric analysis, field-emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. The data obtained from the thermal analysis of PVP/PANs indicated their noteworthy thermal stability, thereby implying the complete miscibility between PVP and the PAN hybrid.

Characterization of Polyesters Obtained by Enzyme-Catalyzed Ring-Opening Polymerization of Pentadecanolide at high Temperature

ABSTRACTDifferences on physicochemical properties of poly(pentadecanolide), PPDL, synthesized by enzymatic ring opening polymerization at two different temperatures, 70 C and 90 C, using Novozyme-430 were assessed. PPDL synthesized at 90°C presents lower molecular weight and crystallinity than the one prepared at 70°C. It was detected by FTIR that PPDL synthesized at 90°C presents a large amorphous phase with more terminal OH groups. A difference in the melting and crystallization behavior was detected by differential scanning calorimetry, DSC, where the melting of the PPDL synthesized at 90°C presents multiple melting and crystallization events at lower temperature than those exhibit by PPDL synthesized at 70°C which presents a well defined single melting and crystallization event. The differences in melting behavior are attributed to the presence of a larger amorphous phase in PPDL synthesized at 90°C due to increased number of terminal OH groups that disrupt the crystalline structure. Thermal stability is also higher in PPDL synthesized at 70°C since the onset of decomposition starts 50°C above that observed in PPDL obtained at 70°C.

The role of hydrophobic alkyl chains in the physicochemical properties of poly(β-amino ester)/DNA complexes

Two degradable poly(β-amino ester)s with an average molecular weight of 2kDa, referred to as B1 and B2, have been synthesized to be tested as non-viral gene delivery systems. B2 polymer exhibits two additional non-polar ethyl groups at both ends. This paper describes the influence of that subtle difference on the compaction ability and temporal stability of the complexes formed with plasmid DNA. Our results suggest that the inclusion of those small hydrophobic fragments into the polycation backbone improves its suitability as synthetic DNA carrier. The improvement is related to the formation and physicochemical properties of the complexes. B2 polyplexes were more stable, the polymer hydrolysis was slowed down and plasmid DNA was better protected which was translated into better transfection efficiencies. Although still not totally understood, the role played by hydrophobic forces is ubiquitous in chemical, biological and physical systems, and they must be considered to design future polymers for gene delivery.

Effect of reaction temperature on the physicochemical properties of poly(pentadecanolide) obtained by enzyme-catalyzed ring-opening polymerization

Differences on physicochemical properties of poly(pentadecanolide) (PPDL) synthesized by enzymatic ring-opening polymerization at two different temperatures, 70 and 90 °C, using Novozyme 435 were assessed. PPDL synthesized at 90 °C presents lower molecular weight and crystallinity than the one prepared at 70 °C. It was detected by FTIR that PPDL synthesized at 90 °C presents a large amorphous phase with more terminal OH groups. A difference in the melting and crystallization behavior was detected by differential scanning calorimetry, where the melting of the PPDL synthesized at 90 °C presents multiple melting and crystallization events at lower temperature than those exhibit by PPDL synthesized at 70 °C which presents a well-defined single melting and crystallization event. The differences in melting and crystallization behavior are attributed to the presence of a larger amorphous phase in PPDL synthesized at 90 °C due to increased number of terminal OH groups that disrupt the crystalline structure. Thermal stability is also higher in PPDL synthesized at 70 °C since the onset of decomposition starts 50 °C above that observed in PPDL obtained at 70 °C.

Chemical Synthesis and Characterization of Novel Antibacterial Polycyclic Polymer

Polyaniline (PAn) and poly(alkyl substituted anilines) were synthesized in aqueous media by chemical polymerization of alkyl substituted aniline in presence of ammonium peroxydisulphate as an oxidant. The products were investigated in terms of morphology, chemical structure, and mechanism of polymerization with scanning electron microscope (SEM), transmission electron microscopy (TEM), fourier transform infrared (FTIR), and UV–visible spectroscopy (UV–vis), respectively. Results indicated that physicochemical properties of poly(alkyl substituted anilines) depend on substituent groups bonded to N-position. In general, alkyl-substituted PAn have similar chemical and optical properties to parent PAn and it seems that the substituted PAn follow the same polymerization mechanism as reported for PAn. The prepared polymers were then tested for the antibacterial properties against Gram-negative bacteria: Escherichia coli (E. coli). The antibacterial properties were assessed by measuring the zones of inhibition. The antimicrobial results showed clearly that PAn and poly(alkyl substituted anilines) exhibited excellent antibacterial activity against the growth of E. coli microorganism.

Effect of poly(amid–imide)/Al2O3 hybrid with various ratios on the physicochemical properties of poly(vinyl alcohol) nanocomposites films

To study the effect of the various ratios of poly(amide–imide)/Al2O3 nanocomposites (PANC)s on the mechanical and thermal properties of nanocomposites films, poly(vinyl alcohol) (PVA)/PANCs based on various ratios of 2, 4, and 6 wt% were prepared and characterized. In the first step, the surface of alumina nanoparticles was treated with 15 wt% of biosafe diacid and consequently, about 10 wt% of these modified nanoparticles were loaded into the poly(amide–imide) matrix. Then, various contents of the obtained PANCs were incorporated into a PVA solution using a sonochemical treatment. The effects of PANC on the structure and morphology of PVA matrix were studied using powder X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, atomic force microscopy (AFM), and thermal gravimetric analysis (TGA). The results show that the tensile strength and decomposition temperature were improved as the portion of PANC into PVA matrix are increased from 2 to 6 wt%. Also, AFM pictures of the fracture surfaces of PVA/PANCs showed a significantly rougher surface than the neat PVA.

Tuning heterogeneous poly(dopamine) structures and mechanics: in silico covalent cross-linking and thin film nanoindentation

Mussel-inspired synthetic poly(dopamine) thin films from dihydroxyphenylalanine (DOPA) and lysine, structurally similar to natural melanin, have drawn extensive interest as a versatile surface functionalization and coating material for use in a broad range of applications. In order to gain a better understanding of its complex and heterogeneous polymeric structure and mechanical properties, we report a computational model of poly(dopamine) by mimicking the polymerization process of the intermediate oxidized product of dopamine, 5,6-dihydroxyindole (DHI), via controlled in silico covalent cross-linking under the two most possible reaction schemes proposed in experiments. To validate our results using experiment, we synthesize poly(dopamine) thin films and perform experimental nanoindentations on the film. We observe an overall linear behavior for Young's modulus as a function of the degree of cross-linking, demonstrating the possibility of enhancing the mechanical robustness of poly(dopamine) materials by increasing the extent of polymerization. At the highest degree of polymerization considered (70%), the model mimics the linear tetrameric model for poly(dopamine) and melanin. At this degree of polymerization, we find a Young's modulus of 4.1-4.4 GPa, in agreement with our nanoindentation results of 4.3-10.5 GPa, previous experiments for natural melanin, as well as simulation results for the cyclic tetrameric melanin model (Chen et al., ACS Nano, 2013). Our results suggest that the non-covalent DHI aggregate model might not be appropriate to represent the structure of poly(dopamine) and melanin-like materials, since it gives a much smaller Young's modulus than the experimental lower bound. Our model not only nicely complements the previous computational work, but also provides new computational tools to study the heterogeneous structural and physicochemical properties of poly(dopamine) and melanin, as well as their formation pathways.

Study on the Electrical, Optical, and Physicochemical Properties of Poly(MMA-co-MAA)/Poly(3,4-ethylenedioxythiophene) Hybrid Thin Films

Poly(3,4-ethylenedioxythiophene) (PEDOT) has good properties as a conductive polymer such as high conductivity, optical transmittance, and chemical stability, while offering relatively weak physicochemical properties. The main purpose of this paper is to improve physicochemical properties such as solvent resistance and pencil hardness of PEDOT. Carboxyl groups in the poly(MMA-co-MAA) polymer chains can effectively crosslink each other in the presence of aziridine, resulting in physicochemically robust PEDOT/poly(MMA-co-MAA) hybrid conductive films. The electrical conductivity, optical properties, and physicochemical properties of the hybrid conductive film were compared by varying the solid content and poly(MMA-co-MAA) portion in the coating precursor solution. From the results, the transparency and surface resistance of the hybrid film show a tendency to decrease with increasing solid content in the coating precursor. Moreover, solvent resistance and hardness were dramatically enhanced by hybridization of PEDOT and crosslinked poly(MMA-co-MAA) due to curing reactions between carboxyl groups. The chemical composition of 30 wt-% of poly(MMA-co-MAA) (MMA:MAA mole ratio 9:1) and 3 wt-% - 5 wt-% of aziridine yields the best physicochemical properties of poly(MMA-co-MAA)/PEDOT hybrid thin films.

Study on the physicochemical properties of poly(methylmethacrylate) (PMMA) modified Pd/Fe nanocomposites: Roles of PMMA and PMMA/ethanol

To probe the roles of poly(methylmethacrylate) (PMMA) and PMMA/ethanol in controlling the physicochemical properties of Pd/Fe nanoparticles (NPs) and explore a feasible approach to fabricating highly reactive Pd/Fe NPs, we modified Pd/Fe NPs with PMMA and PMMA/ethanol via aqueous chemical reduction. The particle dispersion and resisting oxidation ability were enhanced by modification with PMMA and PMMA/ethanol, and the 2,4-dichlorophenol dechlorination efficiency increased with the increased molar ratio of PMMA to iron and ethanol to iron. During the preparation, the roles of PMMA and PMMA/ethanol were to control particle agglomeration and oxidation, while those for the dechlorination process were to offer more reactive surfaces and access of active reaction sites to contaminants. Compared to the unmodified process, the modification process resulted in a different dechlorination process mainly resulted from the roles of PMMA and PMMA/ethanol in regulating properties of Pd/Fe NPs. In addition, the roles of PMMA and PMMA/ethanol in 2,4-dichlorophenol dechlorination kinetics using Pd/Fe NPs were revealed. The ethanol introduced enhanced the particle resisting oxidation ability and prolonged its longevity. These results demonstrated that the PMMA and ethanol had played a favorable role in promoting colloidal stability and improving dechlorination ability of Pd/Fe NPs.

Physicochemical Properties of Poly(lactic acid-co-glycolic acid) Film Modified via Blending with Poly(butyl acrylate-co-methyl methacrylate)

A series of poly(lactic acid-co-glycolic acid) (PLGA)/poly(butyl acrylate-co-methyl methacrylate) (P(BA-co-MMA)) blend films with different P(BA-co-MMA) mole contents were prepared by casting the polymer blend solution in chloroform. Surface morphologies of the PLGAP(BA-co-MMA) blend films were studied by scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PLGAP(BA-co-MMA) blend films were investigated by differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), tensile tests, and surface contact angle tests. The introduction of P(BA-co-MMA) could modify the properties of PLGA films.

Effects of gamma ray and electron beam irradiation on the mechanical, thermal, structural and physicochemical properties of poly (ether-block-amide) thermoplastic elastomers

Both gamma ray and electron beam irradiation are widely used as a means of medical device sterilisation. However, it is known that the radiation produced by both processes can lead to undesirable changes within biomedical polymers. The main objective of this research was to conduct a comparative study on the two key radiosterilisation methods (gamma ray and electron beam) in order to identify the more detrimental process in terms of the mechanical, structural, chemical and thermal properties of a common biomedical grade polymer. Poly (ether-block-amide) (PEBA) was prepared by injection moulding ASTM testing specimens and these were exposed to an extensive range of irradiation doses (5–200kGy) in an air atmosphere. The effect of varying the irradiation dose concentration on the resultant PEBA properties was apparent. For instance, the tensile strength, percentage elongation at break and shore D hardness can be increased/decreased by controlling the aforementioned criteria. In addition, it was observed that the stiffness of the material increased with incremental irradiation doses as anticipated. Melt flow index demonstrated a dramatic increase in the melting strength of the material indicating a sharp increase in molecular weight. Conversely, modulated differential scanning calorimetry established that there were no significant alterations to the thermal transitions. Noteworthy trends were observed for the dynamic frequency sweeps of the material, where the crosslink density increased according to an increase in electron beam irradiation dose. Trans-vinylene unsaturations and the carbonyl group concentration increased with an increment in irradiation dose for both processes when observed by FTIR. The relationship between the irradiation dose rate, mechanical properties and the subsequent surface properties of PEBA material is further elucidated throughout this paper. This study revealed that the gamma irradiation process produced more adverse effects in the PEBA material in contrast to the electron beam irradiation process.

Effect of copolymerization and semi-interpenetration with conducting polyanilines on the physicochemical properties of poly( N-isopropylacrylamide) based thermosensitive hydrogels

Thermosensitive hydrogels are made by radical homopolymerization of N-isopropylacrylamide (NIPAAM) or copolymerization of NIPAAM with 2-acrylamido-2-methyl-propane sulfonic acid (AMPS). The networks are semi-interpenetrated (s-IPN) with linear conducting polymers: polyaniline (PANI) or poly( N-methylaniline) (PNMANI). The semi-interpenetration affect slightly the phase transition temperature (measured by DSC) of the hydrogels, while water uptake capacity is strongly affected and depends on the relative hydrophobicity of the conducting polymer. Since polyanilines can be protonated in aqueous media, the swelling capacity of the s-IPN hydrogel depends strongly on pH unlike the unmodified hydrogel. The release of a model compound (tris(2,2′-bipyridine)ruthenium (II), Ru ( bpy ) 3 + 2 ), driven by swelling or temperature, is also strongly affected both by the introduction of sulfonic groups, by copolymerization of NIPAAM with AMPS, semi-interpenetration and on the hydrophobicity of the conducting polymer. In that way, composite materials with quite different ion exchange behavior can be made by copolymerization and conducting polymer interpenetration.

Influence of electron beam irradiation on physicochemical properties of poly(trimethylene carbonate)

Electron beam (EB) irradiation of poly(trimethylene carbonate) (PTMC), an amorphous, biodegradable polymer used in the field of biomaterials, results in predominant cross-linking and finally in the formation of gel fraction, thus enabling modification of physicochemical properties of this material without significant changes in its chemical structure. PTMC films ( M w : 167–553 kg mol −1) were irradiated with different doses using an electron accelerator. Irradiation with a standard sterilization dose of 25 kGy caused neither significant changes in the chemical composition of the polymer nor significant deterioration of its mechanical properties. Changes in viscosity-, number-, weight-, and z-average molecular weights of PTMC for doses lower than the gelation dose ( D g ) as well as gel–sol analysis and swelling tests for doses above D g indicate domination of cross-linking over degradation. EB irradiation can be considered as an effective tool for increasing the average molecular weight of PTMC and sterilization of PTMC-based biomaterials.

Effect of the molecular weight on the physicochemical properties of poly(lactic acid) nanoparticles and on the amount of ovalbumin adsorption

Poly(lactic acid) (PLA) nanoparticles were prepared to be used as potential platform for vaccine systems. Commercial high molecular weight PLA (PLAHMW) with Mw 1.5 × 105 and low molecular weight poly(lactic acid) (PLALMW) with Mw 9.3 × 103 were obtained by direct polycondensation from D,L lactic acid and used to prepare nanoparticles by solvent displacement method. The effect of the molecular weight on the physicochemical properties of the polymers, on the nanoparticles dispersions and the amount of ovalbumin (OVA) adsorption was studied. The PLAHMW and PLALMW were characterized by Fourier transformed infrared spectroscopy (FTIR), thermogravimetrical analysis (TGA), modulated temperature differential scanning calorimetry (MTDSC) and gel permeation chromatography (GPC). The particle size distribution and ζ-potential of the obtained dispersions were measured by dynamic light scattering (DLS) and electroacoustic spectroscopy, respectively. The ovalbumin adsorption on nanoparticles was evaluated by the Bradford method. PLALMW dispersion showed lower ζ-potential values and larger sizes compared to PLAHMW dispersion. A minor OVA adsorption was achieved for PLALMW.

Effect of polyethylene glycol (PEG) chain organization on the physicochemical properties of poly( d, l-lactide) (PLA) based nanoparticles

The aim of the present study is to evaluate the effect of polyethylene glycol (PEG) chain organization on various physicochemical aspects of drug delivery from poly( d, l-lactide) (PLA) based nanoparticles (NPs). To reach that goal, two different pegylated polymers of poly( d, l-lactide) (PLA) were synthesized. Polymers used in this study are grafted ones in which PEG was grafted on PLA backbone at 7% (mol/mol of lactic acid monomer), PEG7%-g-PLA, and multiblock copolymer of both PLA and PEG, (PLA–PEG–PLA) n with nearly similar PEG insertion ratio and the same PEG chain length. Blank and ibuprofen-loaded NPs were prepared from both polymers and their properties were compared to PLA homopolymer NPs as a control. Encapsulation efficiency of ibuprofen was found to be ∼25% for (PLA–PEG–PLA) n NPs and ∼80% for PEG7%-g-PLA NPs. (PLA–PEG–PLA) n NPs either blank or loaded showed larger hydrodynamic diameter (∼200 nm) than PEG7%-g-PLA NPs (∼135 nm). A significant difference was observed in the amount of PVA associated with the surface of both NPs where 3.6% and 0.4% (wt/wt) were found on the surface of PEG7%-g-PLA and (PLA–PEG–PLA) n NPs, respectively. No observed difference in zeta potential values for both NPs formulations was found. DSC showed the existence of the drug in a crystalline state inside NPs matrix irrespective of the type of polymer used with either shifting or/ and broadening of the drug melting endotherm. Both AFM phase imaging and XPS studies revealed the possibility of existence of more PEG chains at the surface of grafted polymer NPs than (PLA–PEG–PLA) n during NPs formation. The in vitro release behavior showed that (PLA–PEG–PLA) n NPs exhibited faster release rates than PEG7%-g-PLA NPs. The physicochemical differences obtained between both polymers were probably due to different chain organization during NPs formulation. Such pegylated NPs made from these two different polymers might find many applications, being able to convert poorly soluble, poorly absorbed substances into promising drugs, improving their therapeutic performance, and helping them reach adequately their target area. Our results suggest that the properties of pegylated PLA-based NPs can be tuned by proper selection of both polymer composition and polymer architecture.

Effect of aqueous solubility of grafted moiety on the physicochemical properties of poly( d, l-lactide) (PLA) based nanoparticles

In order to evaluate the solubility effect of grafted moiety on the physicochemical properties of poly( d, l-lactide) (PLA) based nanoparticles (NPs), two materials of completely different aqueous solubility, polyethylene glycol (PEG) and palmitic acid were grafted on PLA backbone at nearly the same grafting density, 2.5% (mol of grafted moiety/mol of lactic acid monomer). Blank and ibuprofen-loaded NPs were fabricated from both polymers and their properties were compared to PLA homopolymer NPs as a control. NPs were analyzed for major physicochemical parameters such as encapsulation efficiency, size and size distribution, surface charge, thermal properties, surface chemistry, % poly(vinyl alcohol) (PVA) adsorbed at the surface of NPs, and drug release pattern. Encapsulation efficiency of ibuprofen was found to be nearly the same for both polymers ∼36% and 39% for PEG2.5%-g-PLA and palmitic acid2.5%-g-PLA NPs, respectively. Lyophilized NPs of palmitic acid2.5%-g-PLA either blank or loaded showed larger hydrodynamic diameter (∼180 nm) than PEG2.5%-g-PLA NPs (∼135 nm). PEG2.5%-g-PLA NPs showed lower % of PVA adsorbed at their surface (∼5%, w/w) than palmitic acid2.5%-g-PLA NPs (∼10%, w/w). Surface charge of palmitic acid2.5%-g-PLA NPs seems to be influenced by the large amount of PVA remains associated within their matrix. Thermal analysis using DSC revealed possible drug crystallization inside NPs. Both AFM phase imaging and XPS studies revealed the tendency of PEG chains to migrate towards the surface of PEG2.5%-g-PLA NPs. While, XPS analysis of palmitic acid2.5%-g-PLA NPs showed the tendency of palmitate chains to position themselves into the inner core of the forming particle avoiding facing the aqueous phase during NPs preparation using O/W emulsion method. The in vitro release pattern showed that PEG2.5%-g-PLA NPs exhibited faster release rates than palmitic acid2.5%-g-PLA NPs. PEG and palmitate chains when grafted onto PLA backbone, different modes of chain organization during NPs formation were obtained, affecting the physicochemical properties of the obtained NPs. The obtained results suggest that the properties of PLA-based NPs can be tuned by judicious selection of both chemistry and solubility profile of grafted material over PLA backbone.