No description available.

Thesis (Ph. D. (Chemistry)) -- University of Limpopo, 2019 / This work presents the synthesis, characterisation and application of poly(vinylidene fluoride-co-hexafluropropylene) (PVDF-HFP) membrane prepared using a phaseinversion method. PVDF-HFP was blended with either functionalised multi-walled carbon nanotubes (MWCNTs), poly-amidoamine (PAMAM) dendrimeric MWCNTs or silver (Ag) nanoparticles and their combinations. Nanocomposite blends such as MWCNTs/PVDF-HFP, PAMAM-MWCNTs/PVDF-HFP, Ag-MWCNTs/PVDF-HFP and Ag-PAMAM-MWCNTs/PVDF-HFP were synthesised successfully. A variety of PVDF-HFP composite membranes prepared were characterised by X-ray powder diffraction (XRD), fourier transform infrared (FTIR), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM) and contact angle. The fMWCNTs, Ag-MWCNTs, PAMAM-MWCNTs and Ag-PAMAMMWCNTs nanocomposites were further characterised by Transmission electron microscopy (TEM) and energy dispersive X-ray (EDX). FTIR spectra of PAMAMMWCNTs confirmed the formation of functional groups such as COOH, NCO, NH2 and PAMAM dendrimer. XRD analysis demonstrated that the crystallite sizes of the silver nanoparticles were larger (8.4 nm) than those of Ag-MWCNTs (7.8 nm) and Ag-PAMAM/MWCNTs (6.4 nm) nanocomposites. These findings were further confirmed by TEM analysis which showed Ag nanoparticles, Ag-MWCNTs and Ag-PAMAM/MWCNTs having diameters of silver particles between 9 to 20 nm, 5 to 10 nm and 4 to 8 nm respectively. The reduced Ag particle sizes was due to the complexation of MWCNTs and PAMAMMWCNTs with Ag metal ions, which correlates with an enhanced surface area in the nanocomposite membranes, leading to good filtration and antibacterial properties. TGA studies demonstrated that the thermal stability of PVDF-HFP composite membrane was greatly enhanced by the addition of PAMAM-MWCNTs. However, the composite membranes consisting of both Ag nanoparticles and MWCNTs on PVDFHFP did not improve the structural stability of PVDF-HFP. All composite membranes have shown stability up to 400 oC. The contact angle, porosity, swellability and water content measurements of the composite membranes were improved showing enhanced hydrophilicity due to addition of MWCNTs, PAMAM-MWCNTs and/or Ag nanoparticles. The scanning electron microscopy (SEM) images have depicted the formation of microporous structure, with few MWCNTs on the surface strongly interacting with PVDF-HFP as demonstrated by TGA, XRD and FTIR data. SEM cross-sections of PVDF-HFP composite membranes showed a mixture of fingure-like microvoids with a membrane diameter of approximately 180 μm. The BET data showed an improved surface area, pore volume and pore sizes of PVDF-HFP composite membranes when blended with fMWCNTs and PAMAM. These membranes also showed high fouling resistance, good desalination and high Cd(II) ions rejections during permeability studies. E. coli filtration studies indicated that 2.5 wt.% Ag-MWCNTs/PVDF-HFP and 1.8 wt.% Ag-PAMAM-MWCNTs/PVDF-HFP composite membranes displayed good microbial load reduction (100%) and excellent antibacterial properties as evidenced by the bacterial growth on the edges of the membranes. The microbial, physicochemical and chemical analysis of surface water samples from Sekhukhune area showed that the water was contaminated with Enterobacteriaeceae, E. coli, total coliform with high turbidity and total suspended solids above the South African national standard (SANS 241) water guidelines. After filtration with 1.8 wt.% Ag-MWCNTs/PVDF-HFP composite membrane, turbidity was reduced to 4 Nephelometric turbidity units (NTU), total suspended solids to 1 mg/L while Enterobacteriaeceae, E. coli and total coliform were undetectable and complied with SANS 241 limits. Chromium concentration levels were reduced from 0.194 to 0.0138 mg/L, after filtration with 1.8 wt.% Ag-PAMAM-MWCNTs/PVDF-HFP composite membrane also within acceptable SANS 241 limits. Adsorption studies of all composite membranes demonstrated that the adsorption processes of Cd(II) ions was well conformed to Freundlich model (R2 = 0.999), which suggests that the sorption process met heterogeneous adsorption. However, for Cr(VI) ions studies, the adsorption process was conformed to both Langmuir (R2 = 0.999) and Freundlich (R2 = 0.998) model which suggest that that the adsorption process meet both monolayer and heterogeneous adsorption. The maximum adsorption capacity fitted by Langmuir isotherm was 166.7 and 9.72 mg/g for Cd(II) ions (at optimum pH 6.5) and Cr(VI) ions (at optimum pH 2.5) respectively, using 1 wt.% PAMAM-MWCNTs/PVDF-HFP composite membrane. The adsorption capacities of Cd(II) ions were higher than those of Cr(VI) ions, which is thought to be due to the properties of the composite membrane material. According to the thermodynamic parameters, the Cd(II) and Cr(VI) ions adsorption process was spontaneous and endothermic. Reusability studies showed that PVDF-HFP composite membranes can be reused at least 4 times with an adsorption loss of only 5% for 1 wt.% PAMAMMWCNTs/PVDF-HFP composite membrane, confirmed by TGA and ICP-OES analysis. The 1 wt.% PAMAM-MWCNTs-PVDF-HFP composite membrane exhibited a higher selectivity towards Cd(II) over Cu(II), Zn(II) and Ni(II) in binary and quaternary metal adsorption studies.

The thermally induced reaction of halogenated ethylenes on the α-Cr₂O₃ (101̅2) single crystal surface results in the formation of gas phase hydrocarbons including acetylene, ethylene, butadiene, and dihydrogen, and deposition of surface chlorine adatoms. No surface carbon or combustion products are observed in any reactions indicating no thermally induced C-C bond cleavage occurs and surface lattice oxygen is not incorporated into surface intermediates. Thermal desorption spectroscopy indicates that in all halogenated ethylene reactions acetylene is the major product, regardless of the reaction scheme. The surface reactions of halogenated ethylenes are proposed to proceed through C-X (X=halogen) bond cleavage to form surface halogen adatoms and surface C2 hydrocarbon fragments. Halogen adatom deposition affects reaction barriers to hydrocarbon formation, and eventually shuts down surface chemistry. Photoemission and near edge x-ray absorption fine structure spectra show that all studied reactants undergo some C-X bond cleavage upon low temperature adsorption forming adsorbed C2 fragments and halogen adatoms. Photoemission for each reaction system shows at least two C1s features (283.0-286.0 eV) and two Cl2p features (2p_3/2=198.0-201.0 eV) with higher binding energy features associated with molecularly intact halogenated ethylenes and lower binding energy features associated with dissociated surface species. Near edge x-ray absorption fine structure spectra taken, corresponding to photoemission spectra, indicate the occurrence of C1s→π∗ transitions, indicating intact π-systems are present. Heating the surface results in a reduction in intensity of higher energy photoemission and near edge x-ray absorption fine structure indicative of a decrease in surface C-X bonds. / Ph. D.

In a push towards more environmentally friendly pyrotechnics, new greener pyrotechnic compositions need to be developed. A primary goal is to replace components such as lead, barium, and chromium in pyrotechnic compositions. Fused Deposition Modelling (FDM) is a 3D printing/additive manufacturing method whereby a thin filament is passed through a heated nozzle, and extruded onto a substrate in successive layers. This method of manufacturing could be used to produce pyrotechnic time delays based on suitable “green” polymer/fuel mixtures. Fluoropolymers are an attractive oxidising system for pyrotechnic use as fluorine is highly reactive and reacts relatively easily with common metallic fuels such as aluminium and magnesium to release a large amount of energy. Fluoropolymers are already in use as oxidisers and binders, especially in infrared decoy flares. PTFE has found wide use in the pyrotechnics industry, but is not melt-processible. A similar fluoropolymer, poly(chloro-trifluoroethylene) (PCTFE) was considered instead. PCTFE differs from PTFE in that one of the fluorine atoms in the TFE monomer has been replaced by a chlorine atom. The larger chlorine atom interferes with the packing of the polymer chains during polymerisation and, as such, may make it easier to process than PTFE. It was found that pure PCTFE degraded heavily during processing and was therefore precluded from any further study. Melt-processible copolymers containing PCTFE are available from industry. These copolymers contain vinylidene fluoride (VDF) in addition to the CTFE i.e. poly(CTFE-co-VDF). Two grades of copolymer were obtained from 3M: FK-800® resin and Dyneon® 31508 resin. These two polymers contain different ratios of CTFE to VDF. FK-800® resin was successfully extruded and showed minimal signs of degradation. Pyrotechnic films, containing aluminium powder as the fuel, were cast with both polymers using solvent techniques. Differential thermal analysis (DTA) was used to determine the ignition points of the compositions. All of the FK-800®-based compositions ignited at approximately 450 °C whilst all the Dyneon® 31508-based compositions ignited at approximately 400 °C. The energy output of the compositions was determined using bomb calorimetry. The experimental energy outputs of the FK-800®-based compositions correlated well with the predictions from the thermodynamic simulations. The maximum energy output, ~7.0 MJ∙kg1, occurred at a fuel loading between 30 – 35 wt.%. Except for one composition, the Dyneon® 31508-based compositions did not ignite in the bomb calorimeter. FK-800® was successfully extruded into a filament and showed minimal signs of degradation. In order to assess the impact of adding a solid filler on the mechanical properties and extrudability of the polymer, magnesium hydroxide was used as inactive model compound in place of aluminium. A filament of FK-800® and Mg(OH)2 was successfully compounded and produced using a filler loading of 30 wt.%. Compounding of the Dyneon 31508® with the magnesium hydroxide was unsuccessful. Addition of LFC-1® liquid fluoroelastomer improved the processibility of the Dyneon 31508® by lowering the melt viscosity. / Dissertation (MEng)--University of Pretoria, 2017. / Chemical Engineering / MEng / Unrestricted

Cette thèse décrit comment la morphologie et le polymorphisme de membranes en fluorure de poly(vinylidène) (PVDF) préparées par séparation de phase induite par la vapeur d'eau (VIPS) et par un non-solvant liquide peuvent être ajustés par la température à laquelle le PVDF est dissous (Tdis) pour former la solution de coulée. Les résultats montrent que Tdis présente une transition, notée comme la température de dissolution critique (Tcri), à partir de laquelle la morphologie et le polymorphisme des membranes changent radicalement. Ce phénomène observé pour les trois solvants, N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), and N,M-dimethylformamide (DMF), et les non-solvants (eau et une série d'alcools) utilisés dans cette étude peut être considéré comme général. La cristallisation a lieu avant la démixtion L-L quelle que soit Tdis. Pour une Tdis supérieure à Tcri, les membranes se présentent sous forme de nodules (cristallite forme beta) dont la taille décroît lorsque Tdis diminue. Ce domaine a été dénommé "à grossissement libre" car les chaînes de polymère peuvent cristalliser librement pendant la séparation de phase. Pour une Tdis inférieure à Tcri, des membranes avec une structure bi-continue (cristallite forme alpha) sont obtenues. Ce domaine a été appelé "à grossissement empêché" dans la mesure où la séparation de phase s'accompagne d'une gélification. Nous avons démontré que la morphologie et le polymorphisme cristallin des membranes de PVDF peuvent ainsi être contrôlés par la Tdis et la vitesse d'échange avec le non-solvant. Ces résultats sont interprétés en termes d'auto germination et de compétition entre gélification, cristallisation et démixtion L-L. / This dissertation shows how the morphology and polymorphism of poly(vinylidene fluoride) (PVDF) membranes prepared by using vapor-induced phase separation (VIPS) and liquid-induced phase separation (LIPS) were tuned by varying the dissolution temperature at which PVDF was dissolved (Tdis) to form the casting solution. We observed a transition temperature denoted by critical dissolution temperature, Tcri, across which the morphology and polymorphism of membranes (obtained by VIPS) drastically changed. The phenomenon was considered as general, as a Tcri was observed for all the three solvents N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), and N,N-dimethylformamide (DMF) and the non-solvents, water and a series of alcohols, used in the present study. No matter which Tdis we used, polymer crystallization occurred prior to the L-L demixing. With Tdis above Tcri, the prepared membranes were composed of nodules (mainly in beta crystalline form) and the size of polymer domains decreased as the Tdis decreased. Because the polymer chains could freely coarsen to a large domain during the phase separation, we called the system free coarsening. With Tdis below Tcri, membranes with lacy (bi-continuous) structure (mainly in alpha crystalline form) were obtained. Because the polymer solution gelled during the phase separation, we called the system hindered coarsening. It was proven that PVDF membrane morphology and crystalline polymorphs can be monitored by Tdis and the solvent-nonsolvent exchange rate. These results were discussed in terms of self-seeding effect and competition between the gelation, crystallisation and L-L demixing.

Les polymères fluorés sont des matériaux possédant des propriétés remarquables, ce qui donne lieu à des nombreuses applications. Cependant, même si la polymérisation radicalaire contrôlée (PRC ou RDRP) a connu un grand développement dès le milieu des années 90, l’obtention de polymères de taille et de structure bien définies pour certains monomères fluorés reste encore un réel défi. C’est le cas du fluorure de vinylidène (VDF), H2C=CF2, qui lors de la polymérisation radicalaire peut conduire à une addition normale (têtequeue) ou des additions inverses (têtetête et queuequeue). Ces défauts d’enchainement provoquent la formation d’espèces dormantes peu réactives lors d’une PRC. Ceci entraine l’accumulation de chaînes dormantes difficiles à réactiver qui conduit à une perte de contrôle et à l’augmentation de la polymolécularité. Des études récentes ont montré que l’utilisation de complexes organométalliques peut minimiser ce problème en rééquilibrant les énergies nécessaires pour réactiver les deux différentes chaînes dormantes. D’autre part, des calculs théoriques ont montré que les complexes de manganèse pentacarbonyle alkyle et fluoroalkyle, [Mn(CO)5R] et [Mn(CO)5RF] respectivement, peuvent former des espèces dormantes normales et inverses dont les énergies d’activation sont proches. Ceci pourrait entrainer un certain degré de contrôle de la polymérisation. Dans cette étude, plusieurs complexes de manganèse du type [Mn(CO)5R] et [Mn(CO)5RF] (R = CH(CH3)(COOCH3), CH(CH3)(OCOCH3) et CH(CH3)(C6H5); RF = CF3, CHF2, CH2CF3 et CF2CH3) ont été synthétisés et parfaitement caractérisés, puis ont été utilisés comme amorceurs de polymérisation de divers monomères et comme modèles de bouts de chaîne en PRC par des complexes organométalliques (OMRP). Pour cela, des mesures expérimentales de l’enthalpie de dissociation homolytique de la liaison MnC ont été réalisées par des méthodes cinétiques. De plus, une étude plus approfondie sur la formation de certains sousproduits lors de la décomposition thermique de complexes de manganèse fluoroalkyle en présence du tris(trimethylsilyl)silane en tant que piégeur de radicaux a été réalisée et soutenue par des calculs théoriques. Ces complexes ont également été testés en polymérisation du VDF et d’autres monomères nonfluorés. / Fluoropolymers are materials characterized by remarkable properties and are involved in many applications. However, although controlled radical polymerization (CRP or RDRP) has been extraordinarily developed since the mid90s, synthesizing welldefined polymers of certain fluorinated monomers still remains a crucial challenge. This is the case of vinylidene fluoride (VDF), H2C=CF2, which under radical polymerization can undergo normal additions (head to tail) or reverse additions (head to head and tail to tail). These chain defects cause the formation of less reactive dormant species during a CRP. This favors an accumulation of less reactive dormant chains and leads to a loss of the control as well as to an increase of the dispersity. Recent studies have concluded that the use of organometallic complexes can minimize this problem by equilibrating the energies needed to reactivate both types of dormant chains. On the other hand, theoretical calculations have shown that alkyl and fluoroalkyl manganese pentacarbonyl complexes, [Mn(CO)5R] and [Mn(CO)5RF] respectively, are able to lead to normal and inverse dormant species with a similar activation energy. This could afford some degree of controlled polymerization. In this study, several manganese complexes ([Mn(CO)5R] and [Mn(CO)5RF], where R = CH(CH3)(COOCH3), CH(CH3)(OCOCH3) and CH(CH3)(C6H5); RF = CF3, CHF2, CH2CF3 and CF2CH3) have been synthesized and fully characterized. They were then used as original initiators for the polymerization of various monomers and as chainend models in CRP mediated by organometallic complexes (OMRP). Experimental measurements of the dissociation enthalpy of the MnC bond were carried out by kinetic methods. In addition, a deeper study of the formation of certain byproducts during the thermal decomposition of the fluoroalkylpentacarbonylmanganese(I) complexes in the presence of tris (trimethylsilyl)silane as a radical trap was carried out and supported by theoretical calculations. These complexes were also tested in the polymerization of VDF and of other nonfluorinated monomers.

The main purpose of this thesis was to investigate and characterize the use of piezoelectric yarn for use in textile (fingertip) pressure sensors in glove applications. Such applications could include healthcare, security and safety, game applications or intelligent control. Piezoelectric materials generate a voltage when pressed or squeezed. Poly(vinylidene fluoride) (PVDF) is a polymorphic material with piezoelectric properties. PVDF yarns were integrated into block sensors. These blocks consist of thermoplastic material glued to a knitted supporting fabric. The electrical signal given off by the PVDF yarn was measured with the help of an oscilloscope. The block sensor generated a distinguishable signal under a dynamic compression of 0.003 N, indicating that the structure is sensitive enough compared to the average male fingertip sensitivity threshold (0.0054N). / Program: Master programme in Textile Engineering

Arbetet syftar till att skapa en prototyp av en textil trycksensor som kan känna av och skilja på olika typer av belastning. En lämplig metod för att på ett vetenskapligt sätt testa sagda prototyp har också utvecklats. Prototypen har tillverkats för hand på en datoriserad vävstol och de ingående materialen är piezoelektrisk poly(vinyldifluorid), PVDF, tvinnad tillsammans med ett konduktivt garn, Shieldex®, samt polyester. När PVDF-fiber utsätts för töjning genererar de en spänning, vars storlek står i relation till töjningen. Den vävda konstruktion som valdes till prototypen är en distansvara där väftinläggen lagts in i 7 olika lager för att skapa volym. Därmed möjliggörs en töjning av PVDF-fibern som relaterar till trycket strukturen utsätts för. För att utvärdera strukturen skapades tre likadana trycksensorer innehållandes fyra PVDF-fiber som lagts in med ett mellanrum på ca 1,5 cm. Dessa prototyper har sedan fästs på en egentillverkad ramp och PVDF- samt Shieldex®-garnet har kopplats in till ett oscilloskop. Därefter har vikter rullats över prototypen för att generera spänning, vilken har kunnat uppmätas med oscilloskopet. De uppmätta resultaten har analyserats och utvärderats med hjälp av Excel. Testerna visade tydligt att spänningen som uppmättes stod i relation till vikternas storlek; högre vikter gav en mätbart större spänning. Det finns dock stor varians bland resultaten och utvärdering av samtliga prover visar på stora standardavvikelser hos samtliga fiber. Detta innebär att även om det är tydligt att ökad vikt medför ökad signal så kan det finnas svårigheter i att avgöra storleken på vikten utifrån den uppmätta spänningen. / The aim of this project was to create a sensor in textile material which can register and recognize different kinds of pressure. A suitable method has been developed in order to scientifically investigate and evaluate the sensitivity of the prototypes. The prototypes have been produced with a computerized hand weave machine and the materials used were polyester and piezoelectric PVDF-fiber, twisted with a conductive yarn, Shieldex®. When a force is applied to the PVDF-fiber, causing an extension of the fiber, a voltage is generated directly related to the applied force. The final prototype is a woven textile with integrated monofilaments and weft inserted in seven different layers to create a voluminous structure. An extension by the PVDF-fiber is there by enabled to occur which is related to the force applied onto the structure. Three equable prototypes were produced, each consisting four separated PVDF-fibers which were inserted with a distance of 1, 5 cm from each other. The prototypes were further attached one by one on a homemade ramp and the PVDF- and Shieldex®-fibers were connected to an oscilloscope. Different weights were then rolled from the top of the ramp, generating a voltage each time it pressures a fiber, which were seen on the computer software of the oscilloscope. The results were afterwards analyzed and evaluated using Excel. A clear relationship between applied force and generated voltage is shown although there is a great variety among the test results on each weight along with large standard deviations. The exact weight generating a specific voltage is therefore difficult to determine.

<div>Carbenes are reactive organic intermediates comprised of a neutral, divalent carbon atom. The reactivity of carbenes is often orthogonal to polar functional groups (nucleophiles and electrophiles), making them valuable intermediates for organic synthesis. For example, carbenes can engage in cheletropic reactions with olefins to form cyclopropane rings or undergo insertions into weak element-hydrogen bonds. The most established strategy for accessing carbene intermediates is through a redox-neutral decomposition of diazoalkanes to form a transient M=CR₂ species. Over the course of nearly a half-century of development, many instrumental synthetic methods have emerged that operate on this basis. Despite the combined utility of these methods, the scope of catalytic carbene transfer reactions remains largely constrained by the inherent instability of the starting materials. Diazoalkanes often require electron-withdrawing groups to provide stability through resonance effects.</div><div>Contrary to redox-neutral methods, reductive carbene transfer reactions utilize non-stabilized 1,1-dihaloalkanes as carbene precursors. The Simmons-Smith cyclopropanation reaction represents the most documented example of this class, and remains today as the most practical method for parent methylene (:CH₂) transfer. Nevertheless, reductive carbene transfer processes have proven to be remarkably resistant to catalysis. Our group is interested in developing first-row transition metal catalysts which can initiate an oxidative addition into 1,1-dihaloalkanes, followed by a two-electron reduction with an outer-sphere reductant to provide access to a M=CR₂ intermediate for carbene transfer.</div><div>The application of this mechanistic hypothesis toward reductive methylene transfer using CH₂Cl₂ as the carbene source and a Ni catalyst is outlined in chapter one. The discovery of an unexpected cyclooligomerization of methylene carbenes is discussed. Mechanistic studies are presented, which are consistent with a pathway in which carbenes are iteratively inserted into an expanding metallacycle. In chapter two, the corresponding activation of 1,1-dichloroalkenes for vinylidene transfer in [5+1]-cycloadditions with vinylcyclopropanes is outlined. Finally, in the third and final chapter, organic reactions catalyzed by complexes which feature metal-metal bonds are reviewed.</div>

Poly (2-ethyl-2-oxazoline)-based amphiphilic diblock copolymer has the potential to form promising membrane materials for water purification due to the thermal stability and good solubility in aqueous solution and also for gas separation because of the presence of polar amide group along the polymer backbone. Moreover, their self-assembly into micelles renders them candidate materials as nanocarriers for drug delivery applications. In this study, a novel well-defined linear PEtOx-based amphiphilic diblock copolymer with a hydrophobic fluoropolymer, i.e., PVDF, have been successfully synthesized by implementing a synthesis methodology that involves the following four steps. In the first step, poly (2-ethyl-2-oxazoline) (PEtOx) was synthesized via living cationic ring-opening polymerization (LCROP) of 2-ethyl-2-oxazoline (EtOx) monomer. The “living” nature of LCROP allows the desirable termination to occur by using the proper termination agent, namely, water, to achieve the polymer with a terminal hydroxyl group, i.e., PEtOx-OH. The hydroxyl end group in PEtOx-OH was converted to PEtOx-Br using 2-bromopropionyl bromide via an esterification reaction. In the third step, the PEtOx-Br macro-CTA was subsequently reacted with potassium ethyl xanthate to insert the necessary RAFT agent via nucleophilic substitution reaction to obtain PEtOx-Xanthate. It s worth mentioning that this step is vital for the sequential addition of the second block via the RAFT polymerization reaction of fluorinated monomer, i.e., VDF, to finally obtain the well-defined amphiphilic diblock copolymer with variable controlled chain lengths. Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR) and Fourier Transform Infrared Spectroscopy (FT-IR) confirmed the structure of the macroinitiator and final copolymer, respectively. Size Exclusion Chromatography (SEC) determined the number-average molecular weight (Mn) and the polydispersity index (PDI) of the obtained copolymer. Furthermore, the polymorphism of the diblock copolymer characterized by X-Ray Diffraction (XRD) indicated that the copolymer displays the electroactive α-phase. The resultant amphiphilic diblock copolymer exhibits spherical micelles morphology, as confirmed by Dynamic Light Scattering (DLS) and Atomic Force Microscopy (AFM). Moreover, Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) investigated the thermal decomposition behavior of the copolymer and determined the glass transition temperature (Tg ≈ 70 °C), melting temperature (Tm ≈ 160-170 °C), and crystallization temperature (Tc ≈ 135-143 °C) of the diblock copolymer, respectively.