Plast- och kompositindustrin har växt i årtionden och den ständigt växande världen och ny teknik kräver ännu större mängder polymerkompositer för en mängd olika tillämpningar. Numera är de negativa miljöaspekterna av polymerproduktion och plastavfall kända, men trots detta är råoljafortfarande det primära råmaterialet för de flesta polymerer. Att hitta biobaserade material medtillräckliga egenskaper för att ersätta de fullt syntetiska materialen är avgörande för en hållbarutveckling. Detta examensarbete studerar både glasfiber och mikrokristallin cellulosaarmerade biooljebaserade polyamider, samt undersöker hur de kan kompatibiliseras, deras mekaniska egenskaper samt användbarheten för additiv tillverkning. Kompatibilisering är en viktig aspekt när två föreningar blandas för att göra en komposit. Enlämplig kompatibilisator kommer att förbättra vidhäftningen vid gränsytan mellan armeringsmaterialet och polymermatrisen och därmed öka de mekaniska egenskaperna hos materialet. Glasfiber / polyamid-kompositen kompatibiliserades med vinyltrimetoxisilan, medanmikrokristallin cellulosa / polyamid-kompositen kompatibiliserades med 4,4'-difenylmetandiiisocyanat. Båda kompositerna analyserades för att erhålla information om termiska, mekaniska och reologiska egenskaper. Yt- och sprickmorfologin undersöktes också. Resultaten indikerar att armeringen resulterade i förbättrade mekaniska egenskaper, även om den önskade kompatibiliseringen inte erhölls i experimentet. Det mest uppmuntrande resultatet var att den biobaserade cellulosaarmeringen förbättrade de mekaniska egenskaperna. Genom visuell undersökning fanns den helt biobaserade polymerkompositen vara mjukare än den glasfiberarmerade. Framtidsutsikterna visar att det finns vissa problem att ta itu med och övervinna för att dessa material ska göras lämpliga för additiv tillverkning. Nyckeln är att hitta en kompatibilisator som tålupprepad bearbetning vid höga temperaturer. För att upprätthålla enhetliga egenskaper krävskorrekt spridning av armeringsmaterialet, vilket uppnås genom att optimera tillverkningsmetoden. Dessutom är cellulosa benägen att termisk nedbrytning, så behandlingstemperaturerna för både armeringsmaterialet och polymermatrisen bör övervägas noggrant. / Plastics and composites have been a growing industry for decades, and the always growing worldand new technologies demand even greater amounts of polymeric composites for a variety ofapplications. Nowadays the negative environmental aspects of polymer production and plastic waste are known, but despite that crude oil is still the primary material for most polymers. Finding biobased materials with sufficient properties to replace the fully synthetic ones is crucial in sustainable development. This master’s thesis studies both glass fiber and microcrystalline cellulose reinforcedbio-oil based polyamide, how they could be compatibilized, the mechanical properties and applicability for additive manufacturing. Compatibilization is an important aspect when two compounds are mixed to make a composite. A proper compatibilizer will enhance the interfacial adhesion between the reinforcement and matrix, thus increasing the mechanical properties of the material. The glass fiber/polyamide11 composite was compatibilized with vinyltrimethoxysilane, and the microcrystalline cellulose/polyamide11 composite was compatibilized with 4,4'-diphenylmethane diisocyanate. Both composites were analyzed to obtain information about thermal, mechanical, and rheological properties. The surface and fracture morphology are examined, as well.The results indicate that reinforcing resulted to enhanced mechanical properties, even though the desired compatibilization was not acquired in the experiment. The most encouraging result was that the bio-based cellulose reinforcement enhanced mechanical properties, by visual examination thefully bio-based polymeric composite was found to be more ductile than the glass fiber reinforcedone. For future prospect, there are few issues to be addressed and overcome for these materials to bemade suitable for additive manufacturing. The key is finding a compatibilizer that can withstand high processing temperatures repeatedly. Maintaining uniform properties requires proper dispersion of reinforcement, which is achieved by optimizing the manufacturing method. In addition, cellulose is prone to thermal degradation, so the processing temperatures for both reinforcement and matrix should be considered carefully. / Muovit ja komposiitit ovat jo vuosikymmenien ajan ollut kasvava teollisuuden ala, ja alatikehittyvä maailma sekä uudenlainen teknologia vaatii entistä enemmän polymeerikomposiittejaerilaisiin käyttökohteisiin. Nykyään polymeerituotannon ja käytöstä poistuvien muovituotteidennegatiivisista ympäristövaikutuksista ollaan tietoisia. Tästä huolimatta raakaöljy on pääraaka-ainepolymeerien valmistuksessa. Ympäristövaikutusten minimoimiseksi olisi tärkeää löytääbiopohjaisia materiaaleja, jotka ominaisuuksiensa puolesta ovat riittäviä korvaamaan täysinsynteettisiä materiaaleja. Tässä työssä on tutkittu sekä lasikuidulla että mikrokiteisellä selluloosallavahvistetun bioöljypohjaisen polyamidin kompatibilisointia ja mekaanisia ominaisuuksia, sekäkyseisten komposiittien soveltuvuutta materiaalia lisääviin valmistusmenetelmiin.Kompatibilisaatio on tärkeää, kun yhdistetään kaksi eri komponenttia yhdeksikomposiittimateriaaliksi. Sen tarkoituksena on vahvistaa molekyylien rajapinnan adheesiotalujitteen ja sidemassan välillä, jolloin materiaalin mekaaniset ominaisuudet paranevat. Lasikuidullalujitettujen polyamidikomposiittien kompatibilisointiin käytettiin vinyylitrimetoksisilaanilla jamikrokiteisellä selluloosalla lujitettu polyamidikomposiitti kompatibilisoitiin 4,4'-difenyylimetaanidi-isosyanaatilla. Molempien komposiittien termiset, mekaaniset ja reologiset ominaisuudetarvioitiin. Lisäksi tutkittiin pinnan ja murtumakohdan morfologiaa.Tulokset osoittavat, että polymeerin lujittaminen parantaa mekaanisia ominaisuuksia, vaikkatavoiteltua kompatibilisaatioita materiaalien välillä ei tapahtunutkaan. Työn lupaavin tulos olibiopohjaisen mikrokiteisen selluloosan tuoma parannus materiaalin kestävyysominaisuuksille.Etenkin silmämääräisesti tarkastellessa täysin biopohjainen polymeerikomposiitti oli taipuisampaakuin lasikuidulla lujitettu komposiitti.Muutamaan asiaan tulee kiinnittää erityisesti huomiota, jos tämänkaltaisia materiaaleja halutaankäyttää materiaalia lisäävissä menetelmissä. Tärkeintä on löytää kompatibilisoija, joka kestääkorkeita lämpötiloja toistuvasti. Lujitteen tasainen dispersio on tärkeää, jotta saadaan aikaantasaista laatua ja ominaisuudet ovat samanlaiset koko materiaalissa. Tämä saavutetaanvalmistusmenetelmän optimoinnilla. Lisäksi tulee ottaa huomioon selluloosan taipumus termiseenhajoamiseen, jolloin sekä lujitteen että sidemassan prosessointilämpötilat tulisi ollasamansuuruiset.

The large amount of non-degradable plastic waste has become a significant environmental concern, leading to an increased need for degradable plastics. Here in, to create degradable polymers, polyesters were produced through radical ring opening polymerization using cyclic ketene acetals. The cyclic ketene acetal monomer 5,6-benzo-2-methylene-1,3-dioxepane has been prepared for the synthesis of homo- and copolymers with methyl methacrylate, α-methylene-γ-valerolactone, α-methylene-γ-butyrolactone, cholesterol methacrylate and limonene acrylate. The polymerization was conducted using radical ring opening polymerization both in bulk and solution polymerization. The structural characteristics of the polymer were determined by different characterization methodologies, including TGA, DSC, SEC, FTIR and 1D 1H-NMR. The results obtained from 1H-NMR analysis showed the composition of the copolymers. TGA analysis revealed the thermal stability of the polymers and their degradation patterns. DSC analysis provided information about the glass transition temperatures (Tg’s) of the polymers. Moreover, the Tg indicated the presence and amounts of comonomers in the copolymers. Overall, the results showed the influence of different comonomers on the properties of the polymers by successfully incorporating the comonomers in the polymer. The thermal properties for polymers containing methyl methacrylate became more thermally stable. The Tg, analyzed with DSC, shifted from the Tg of homopolymers indicating the incorporation of both monomers. The polymers were successfully degraded via hydrolysis in alkaline conditions breaking them down into smaller pieces making them easier to recycle. To conclude, the results all indicate that the incorporation of BMDO and thereby possibly other CKA-monomers into the polymer chains of commonly used plastics could provide valuable tools in the recycling of said plastics.

Hot melt adhesives (HMA) are a class of adhesives that, unlike solvent-or waterborne counterparts, do not contain organic solvents or other carriers, and are produced and subsequently applied in a molten state. The main components of HMA are polymers, tackifying resins, and a plasticiser. HMA offer a more environmentally friendly option of adhesive materials.  This study was undertaken to investigate the performance of plasticisers based on renewable resources in HMA. Historically, mineral oil-based plasticisers have been used with great success in HMA formulations, offering a performance benchmark. This work selected suitable alternatives from renewable resources, ranging from fully renewable to fully conventional compositions. During the production stage, the compatibility of such plasticisers with the rest of the HMA formulation was studied while rheological methods were used to investigate the impact of different plasticisers on the properties of the final HMA. Adhesive properties were also assessed by loop tack and peel tests on polyethylene terephthalate (PET) and stainless steel (SS) substrates.   It was shown that some of the studied materials from renewable resources could offer a suitable component in the design of a biobased plasticiser, whose performance matched conventional plasticisers, while the ratio of the biobased fraction was up to 70 % and possibly even higher. The findings of this work show the potential of biobased alternatives in making HMA with a higher degree of sustainability. / Smältlim är en klass av lim som, till skillnad från lösningsmedels-eller vattenburna motsvarigheter, inte innehåller organiska lösningsmedel eller andra bärare, och som produceras och appliceras därefter i smält tillstånd. Huvudkomponenterna i HMA är polymerer, klibbgivande hartser och en mjukgörare. smältlim erbjuder ett mer miljövänligt alternativ för limmaterial. Denna studie genomfördes för att undersöka prestandan hos mjukgörare baserade på förnybara resurser i HMA. Historiskt har mineraloljebaserade mjukgörare använts med stor framgång i HMA-formuleringar, vilket ger ett prestandariktmärke. Lämpliga alternativ valdes ut från förnybara resurser, allt från helt förnybara till helt konventionella kompositioner. Under produktionsstadiet studerades kompatibiliteten av sådana mjukgörare med resten av smältlimsformuleringen medan reologiska metoder användes för att undersöka olika mjukgörares inverkan på egenskaperna hos det slutliga limmet. Vidhäftningsegenskaperna utvärderades också genom loop tack test och peel test på polyetylentereftalat (PET) och rostfritt stål (SS) substrat. Det visades att en del av de studerade materialen från förnybara resurser kunde erbjuda en lämplig komponent i designen av en biobaserad mjukgörare, vars prestanda matchade konventionella mjukgörare, medan förhållandet mellan den biobaserade fraktionen var upp till 70 % och möjligen ännu högre. Resultaten av detta arbete visar potentialen hos biobaserade alternativ för att göra HMA med en högre grad av hållbarhet.

It is well known that ions affect polymers in specific ways not solely based on electric charge, usually referred to as the Hoffmeister effect or ion specific effects. Poly(N-isopropylacrylamid) (PNIPAM) is a thermosensitive polymer with a LCST at 32℃. PNIPAM is a well studied polymer due to its similarities with denaturation of proteins in aqueous solutions. Utilizing diffusion NMR this report studied the effect different Hoffmeister anion concentrations have on the configuration of pre-transitional PNIPAM. A fractionation process was developed for PNIPAM, yielding a product of about 87 000 g/mol, used for diffusion measurements. Diffusion coefficients for PNIPAM in saline solutions ranging from 0 to 800 mM were measured for NaCl, NaClO4, NaSCN and NaI. Diffusion coefficients for PNIPAM were also measured at some concentrations of NaF, Na2SO4 and Na2CO3. Hydrodynamic radius was calculated from the diffusion coefficients. The report found a pre-transitional chain collapse of PNIPAM which increased with ionic concentrations of NaCl, NaClO4, NaSCN, NaF and Na2CO3, but not for NaI and Na2SO4. At 800 mM the hydrodynamic radius decreased with 9% for NaCl, 13% for NaClO4 and 5% for NaSCN. The hydrodynamic radius decreased with 19% at 300 mM Na2CO3 and with 10% at 400 mM NaF. There was a significant decrease in hydrodynamic radius for high concentrations of NaCl and NaClO4 but exact decrease needs to be replicated to validate the findings due to an unexpected large decrease in hydrodynamic radius already at 50 mM. Values for NaF and Na2CO3 should be replicated with internal standard to accomodate for possible precipitation of the longer polymer chains within the fraction.

Under flera månaders tid har ett kandidatexamensarbete utförts med syftet att optimera produktionen av protein-nanofibrer av vassleproteinisolat. Vassleproteinisolat består till stor del av proteinet β-laktoglobulin. Detta protein kan under upphettning bilda nanofibrer i sur miljö. Det var därför med avseende på parametrarna värme, koncentration och inkubationstid som processen optimerades eftersom det redan existerar ett pH-optimum vid pH-värdet 2. Lösningar av vassleproteinisolat med olika koncentrationer inkuberades under 24 timmar vid fyra olika temperaturer. Samtliga lösningar hade pH-värdet 2. För varje temperatur och inkubering togs proverna ut en åt gången för att sedan analyseras. De olika proverna analyserades sedan med Thioflavin T fluorescens för att se indikationer på fibrillering. De erhållna ThT spektrumen visade på fibrillbildning och resultaten för detta experiment visar på att utbytet av fibrilleringsreaktionen blir högre i takt med att hydrolysens hastighetskonstant blir lägre samt att lägre temperaturer kan gynna fibrillbildning . Ytterligare försök, tid och resurser bör läggas ner på detta område för att med säkerhet kunna optimera produktionen av nanofibrer av vassleproteinisolat. / This bachelor’s degree project’s aim was to optimize the production of protein nanofibrils originating from whey protein isolate. Whey protein isolate largely consists of the protein β-lactoglobulin, which can form nanofibrils while immersed in an acidic environment when heated. Therefore, the process was attempted to be optimized with regards to the yield of the final product of protein nanofibrils by varying parameters such as incubation time, initial concentration and temperature, with a constant pH-value of 2. Solutions of the whey protein isolate at different concentrations were incubated during a time interval of 24 hours and at different temperatures. For every temperature and time period of incubation, one sample at a time was taken out to be measured and analyzed, a total of four samples per initial concentration. The samples were analyzed with Thioflavin T fluorescence to see indications of the existence of fibrillation. The obtained ThT spectra showed intensity diagrams that can be related to the amount of formed nanofibrils, and this experiment shows that the yield of fibrils increases while the rate constant of the hydrolysis decreases, and that the fibrillation is favoured by lower temperatures. To optimize the production of nanofibrils of whey protein with certainty, further experiments, time and resources should be invested in this area.

The relatively new and still growing field of 3D-printing has opened up the possibilities to manufacture patient-specific medical devices with high geometrical accuracy in a precise and quick manner. Additionally, biocompatible materials are a demand for all medical applications while biodegradability is of importance when developing scaffolds for tissue growth for instance. With respect to this, this project consisted of developing biocompatible and bioresorbable polymer blend and composite filaments, for fused deposition modeling (FDM) printing. Poly(lactic acid) (PLA) and polycaprolactone (PCL) were used as supporting polymer matrix while hydroxyapatite (HA), a calcium phosphate with similar chemical composition to the mineral phase of human bone, was added to the composites to enhance the biological activity. PLA and PCL content was varied between 90–70 wt% and 10-30 wt%, respectively, while the HA content was 15 wt% in all composites. All materials were characterized in terms of mechanical properties, thermal stability, chemical composition and morphology. An accelerated degradation study of the materials was also executed in order to investigate the degradation behavior as well as the impact of the degradation on the above mentioned properties. The results showed that all processed materials exhibited higher mechanical properties compared to the human trabecular bone, even after degradation with a mass loss of around 30% for the polymer blends and 60% for the composites. It was also apparent that the mineral accelerated the polymer degradation significantly, which can be advantageous for injuries with faster healing time, requiring only support for a shorter time period.

The extracellular matrix is (ECM) is a network of large, structural proteins and polysaccharides, important for cellular behavior, tissue development and maintenance. Present thesis describes work exploring ECM as scaffolds for tissue engineering by manipulating cells cultured in vitro or by influencing ECM expression in vivo. By culturing cells on polymer meshes under dynamic culture conditions, deposition of a complex ECM could be achieved, but with low yields. Since the major part of synthesized ECM diffused into the medium the rate limiting step of deposition was investigated. This quantitative analysis showed that the real rate limiting factor is the low proportion of new proteins which are deposited as functional ECM. It is suggested that cells are pre-embedded in for example collagen gels to increase the steric retention and hence functional deposition. The possibility to induce endogenous ECM formation and tissue regeneration by implantation of growth factors in a carrier material was investigated. Bone morphogenetic protein-2 (BMP-2) is a growth factor known to be involved in growth and differentiation of bone and cartilage tissue. The BMP-2 processing and secretion was examined in two cell systems representing endochondral (chondrocytes) and intramembranous (mesenchymal stem cells) bone formation. It was discovered that chondrocytes are more efficient in producing BMP-2 compared to MSC. The role of the antagonist noggin was also investigated and was found to affect the stability of BMP-2 and modulate its effect. Finally, an injectable gel of the ECM component hyaluronan has been evaluated as delivery vehicle in cartilage regeneration. The hyaluronan hydrogel system showed promising results as a versatile biomaterial for cartilage regeneration, could easily be placed intraarticulary and can be used for both cell based and cell free therapies.

<p>Degradable polymers have gained an increased attention in the field of biomedical applications over the past decades, for example in tissue engineering. One way of improving the biocompatibility of these polymers is by chemical surface modification, however the risk of degradation during the modification procedure is a limiting factor. In some biomedical applications, for example in nerve guides, a patterned surface is desired to improve the cell attachment and proliferation.</p><p>In this thesis a new non-destructive, single-step, and solvent free method for surface modification of degradable polymers is described. Poly(L-lactide) (PLLA) substrates have been functionalized with one of the following vinyl monomers; N-vinylpyrrolidone (VP), acrylamide (AAm), or maleic anhydride (MAH) grafts. The substrates were subjected to a vapor phase atmosphere constituted of a mixture of a vinyl monomer and a photoinitiator (benzophenone) in a closed chamber at very low pressure and under UV irradiation. Poly(ε-caprolactone) (PCL), poly(lactide-co-glycolide) (PLGA), and poly(trimethylene carbonate) (PTMC) have been surface modified with VP using the same procedure to show the versatility of the method. The wettability of all of the four substrates increased after grafting. The surface compositions were confirmed by ATR-FTIR and XPS. The VP grafted PLLA, PTMC and PLGA substrates have been shown to be good substrates for the normal human cells i.e. keratinocytes and fibroblasts, to adhere and proliferate on. The topography of substrates with well defined nano patterns was preserved during grafting, since the grafted layer is very thin. We have also shown that the method is useful for a simultaneous chemical and topographical modification of substrates by masked vapor phase grafting. The surface topography was determined with SEM and AFM.</p> / <p>Intresset för användningen av nedbrytbara polymerer till biomedicinska applikationer som till exempel vävnads rekonstruktion har ökat avsevärt de senaste decennierna. Ett sätt att öka biokompatibiliteten hos dessa polymerer är genom kemisk ytmodifiering, men risken för nedbrytning under själva modifieringen är en begränsande faktor. I vissa biomedicinska applikationer, till exempel nervguider, är det önskvärt att ha en väldefinierad ytstruktur för att öka vidhäftningen och tillväxten av celler.</p><p>I den här avhandlingen presenteras en ny ickeförstörande, lösningsmedelsfri enstegsprocess för ytmodifiering av nedbrytbara polymerer. Substrat av poly(L-laktid) (PLLA) har ytfunktionaliserats med var och en av följande vinylmonomerer, N-vinylpyrrolidon (VP), akrylamid (AAm) eller maleinsyraanhydrid (MAH). Substraten har exponerats för en gasfasatmosfär av en blandning av en vinylmonomer och en fotoinitiator (bensofenon) i en tillsluten reaktor vid mycket lågt tryck och under UV-strålning. Metodens mångsidighet har även påvisats genom att ytmodifiera substrat av poly(ε-kaprolakton) (PCL), poly(laktid-co-glykolid) (PLGA) och poly(trimetylen karbonat) (PTMC) med VP. Vätbarheten ökade för alla fyra materialen efter ympning med en vinylmonomer. Ytsammansättningen fastställdes med ATR-FTIR och XPS. De VP ympade filmerna av PLLA, PLGA och PTMC visade sig vara bra substrat för mänskliga celler, i detta fall keratinocyter och fibroblaster, att vidhäfta och växa på. Yttopografin hos filmer med väldefinierade nanomönstrade ytor kunde bevaras efter ympning, tack vare att det ympade lagret är så tunt. Gasfas metoden har också visat sig användbar för att simultant ytmodifiera både kemiskt och topografiskt genom maskad gasfasympning. Yttopografin bestämdes med SEM och AFM.</p>

Conductive polymers are also known as "organic metals" due to their semiconducting properties. They are found in a wide range of applications in the field of organic electronics. However, the growing number of experimental works is not widely supported with theoretical calculations. Hence, the field of conductive polymers is experiencing lack of understanding of mechanisms occurring in the polymers. In this PhD thesis, the aim is to increase understanding of conductive polymers by performing theoretical calculations.        The polymers poly(3,4-ethylenedioxythiophene) (PEDOT) together with its selenium (PEDOS) and tellurium (PEDOTe) derivatives, poly(p-phenylene) (PPP) and naphthobischalcogenadiazoles (NXz) were studied. Several computational methods were applied for analysis of mentioned structures, including density functional theory (DFT), tight-binding modelling (TB), and Car-Parrinello molecular dynamics (CPMD) calculations. The combination of CPMD and DFT calculations was applied to investigate the PEDOT, PEDOS and PEDOTe. The polymers were studied using four different functionals in order to investigate the full picture of structural changes, electronic and optical properties. Temperature effects were studied using molecular dynamics simulations. Wide statistics for structural and molecular orbitals analysis were collected.         The TB method was employed for PPP. The formation and motion of the excitations, polarons and bipolarons, along the polymer backbone was investigated in presence of electric and magnetic fields. The influence of non-magnetic and magnetic impurities was determined.        The extended π-conjugated structures of NXz were computed using B3LYP and ωB97XD functionals in combination with the 6-31+G(d) basis set. Here, the structural changes caused by polaron formation were analyzed. The combined analysis of densities of states and absorption spectra was used for understanding of the charge transition. / <p>QC 20170928</p>

Degradable polymers have gained an increased attention in the field of biomedical applications over the past decades, for example in tissue engineering. One way of improving the biocompatibility of these polymers is by chemical surface modification, however the risk of degradation during the modification procedure is a limiting factor. In some biomedical applications, for example in nerve guides, a patterned surface is desired to improve the cell attachment and proliferation. In this thesis a new non-destructive, single-step, and solvent free method for surface modification of degradable polymers is described. Poly(L-lactide) (PLLA) substrates have been functionalized with one of the following vinyl monomers; N-vinylpyrrolidone (VP), acrylamide (AAm), or maleic anhydride (MAH) grafts. The substrates were subjected to a vapor phase atmosphere constituted of a mixture of a vinyl monomer and a photoinitiator (benzophenone) in a closed chamber at very low pressure and under UV irradiation. Poly(ε-caprolactone) (PCL), poly(lactide-co-glycolide) (PLGA), and poly(trimethylene carbonate) (PTMC) have been surface modified with VP using the same procedure to show the versatility of the method. The wettability of all of the four substrates increased after grafting. The surface compositions were confirmed by ATR-FTIR and XPS. The VP grafted PLLA, PTMC and PLGA substrates have been shown to be good substrates for the normal human cells i.e. keratinocytes and fibroblasts, to adhere and proliferate on. The topography of substrates with well defined nano patterns was preserved during grafting, since the grafted layer is very thin. We have also shown that the method is useful for a simultaneous chemical and topographical modification of substrates by masked vapor phase grafting. The surface topography was determined with SEM and AFM. / Intresset för användningen av nedbrytbara polymerer till biomedicinska applikationer som till exempel vävnads rekonstruktion har ökat avsevärt de senaste decennierna. Ett sätt att öka biokompatibiliteten hos dessa polymerer är genom kemisk ytmodifiering, men risken för nedbrytning under själva modifieringen är en begränsande faktor. I vissa biomedicinska applikationer, till exempel nervguider, är det önskvärt att ha en väldefinierad ytstruktur för att öka vidhäftningen och tillväxten av celler. I den här avhandlingen presenteras en ny ickeförstörande, lösningsmedelsfri enstegsprocess för ytmodifiering av nedbrytbara polymerer. Substrat av poly(L-laktid) (PLLA) har ytfunktionaliserats med var och en av följande vinylmonomerer, N-vinylpyrrolidon (VP), akrylamid (AAm) eller maleinsyraanhydrid (MAH). Substraten har exponerats för en gasfasatmosfär av en blandning av en vinylmonomer och en fotoinitiator (bensofenon) i en tillsluten reaktor vid mycket lågt tryck och under UV-strålning. Metodens mångsidighet har även påvisats genom att ytmodifiera substrat av poly(ε-kaprolakton) (PCL), poly(laktid-co-glykolid) (PLGA) och poly(trimetylen karbonat) (PTMC) med VP. Vätbarheten ökade för alla fyra materialen efter ympning med en vinylmonomer. Ytsammansättningen fastställdes med ATR-FTIR och XPS. De VP ympade filmerna av PLLA, PLGA och PTMC visade sig vara bra substrat för mänskliga celler, i detta fall keratinocyter och fibroblaster, att vidhäfta och växa på. Yttopografin hos filmer med väldefinierade nanomönstrade ytor kunde bevaras efter ympning, tack vare att det ympade lagret är så tunt. Gasfas metoden har också visat sig användbar för att simultant ytmodifiera både kemiskt och topografiskt genom maskad gasfasympning. Yttopografin bestämdes med SEM och AFM. / QC 20101014