Diploma thesis is focused on modification and characterization of polypropylene (PP) products surfaces by the chemical way. In theoretical part of thesis are summarized the current knowledge of this topic including characterization methods. Polypropylene surfaces were modified by acrylic monomers (acrylic acid, acrylic acid with 20 mol% content of sodium acrylate and acryl amide). Modified surfaces were characterized by infrared spectroscopy with ATR technique. The comparative parameter was carbonyl index determined from absorption peaks of functional methyl groups (2950 cm-1 ) and functional carbonyl groups (1700-1750 cm-1) of FTIR-ATR spectra. Determination of effect of initiator concentration on the modification process was done for acetophenone and benzophenone. There were determined the time dependence of carbonyl index for time from 0 to 600 s of mentioned monomers. In the same condition were modified test specimens designed for preparation of adhesive joints. Joints were bonded by cyanoacrylate adhesive that provide reaction with surface of polyacrylic acid. There were founded conditions of modification that provided strength of adhesive joints higher than strength of original PP. There were identified changes of surface roughness by using of confocal microscopy.

This diploma work deals with relationship between composition and mechanical properties of polymeric composite with polypropylene matrix and magnesia hydroxide as a filler. The influence of content of filler (20,40,60 w.%) and temperature (-30°C +60°C) on dynamic fracture toughness is observed. The regresion function describing the dependence of studied mechanical properti on temperature for all experimental materials where found. Experimental data were confront with data gained on the same materials then 10 years ago and influence of time on mechanical properties of follow - up composites is evaluate.

The project developed in terms of engineering study of field N2307- 00 Engineering Technology submits a design of components from plastic production technology- cover on the table. The introductory part of this study describes characteristics, division and possible plastics processing. The work consists of production technology proposal (injection into metal mold) and its construction solution. The another part proposes suitable injection material and verification of injection machine. The final part of work consists of financial evaluation of injection process, appropriate blue prints and appendices.

is is a study of the relationship between structure, mechanical properties and relaxing behavior of the polypropylene. The structure was evaluated by the quantity the solid phase content (SPC). This was defined as mathematical result of free induction decay (FID) signal from pulsed 1H-NMR. The solid phase content is a quite new structural parameter representing the quantity for description of semi-crystalline polymers. Whereas pulsed 1H-NMR is non-destructive, accurate and repeatable, it becomes a unique tool for a description of mechanical, structural, physical-mechanical changes of polypropylene within the time and temperature. Particularly, this method registers the small changes in the time-dependant shipments during secondary crystallization with small structure changes.

Gewebeverstärkte Thermoplaste lassen sich durch Thermoformen zu räumlich gekrümmten Bauteilen verarbeiten. Durch die eingehende Analyse des Thermoformvorgangs konnte die Einsicht in die parallel verlaufenden Teilprozesse verstärkt werden. Interlaminare Scherung, der Wärmeaustausch und die Reibvorgänge zwischen Laminat und Werkzeug und die Stempeldeformationen werden eingehend experimentell untersucht. Für die Untersuchung der Reibverhältnisse zwischen Laminat und Werkzeug und des interlaminaren Gleitens werden neue Versuchsanordnungen vorgestellt. Außerdem wurden theoretische Modelle hinsichtlich ihrer Eignung zur Beschreibung dieser Effekte untersucht und gegebenenfalls angepasst. Durch die Aufteilung des Gesamtprozesses in zeitliche Phasen und die Entkopplung der physikalischen Vorgänge in der Beschreibung konnte ein Ansatz zur mathematischen Beschreibung des Gesamtprozesses gefunden werden, der für eine Implementierung in Simulationsprogrammen geeignet erscheint. Aus den gewonnenen Erkenntnissen werden praktische Schlussfolgerungen für die Gestaltung von Werkzeugen und Prozessen abgeleitet.

In this work the possibility for using natural fiber-reinforced thermoplastics in highly loaded large surface structural elements is demonstrated. A production process to fabricate an inexpensive semi-finished material made of polypropylene and unidirectionally orientated natural fibers was developed. The feasibility of the process was proven for different fiber contents. In further examinations optimal parameters for processing the semi-finished material to produce composites by press forming were examined. With these optimal parameters composites have been fabricated that were tested for their static and dynamic properties. On the basis of the characteristic values of these examinations the field of application for natural fiber reinforced thermoplastics in use of large surface structural elements could be shown. As an example for such an element a rotor blade of a wind turbine with a length of 3,75 m was created. For a prediction of the behaviour of the loaded rotor blade the following load cases were simulated by means of the FEM: - 50-year gust, with a wind velocity of 50 m/s and standing rotor - Nominal load, with a wind velocity of 11 m/s and turning rotor. For an evaluation of the composite behaviour the Tsai Wu criterion was used, because of its capability to determine the failure condition under multi-axle stress. With these simulations it could be shown that it is theoretically possible to use natural fiber-reinforced thermoplastics as material for large surface structural elements. / In der vorliegenden Arbeit wurde eine Möglichkeit für die Verwendung von naturfaserverstärkten Thermoplasten in hochbelasteten großflächigen Strukturbauteilen aufgezeigt. Es wurde ein Verfahren entwickelt, welches die preiswerte Herstellung eines Halbzeuges aus Polypropylen und unidirektional ausgerichteten Naturfasern ermöglicht. Die Realisierbarkeit dieses Verfahrens konnte für verschiedene Naturfasergehalte nachgewiesen werden. In weiteren Untersuchungen wurden die optimalen Verarbeitungsparameter für die Herstellung von Faserverbunden aus diesem Halbzeug mittels der Presstechnik ermittelt. Mit diesen optimalen Parametern wurden Verbunde hergestellt und auf ihre statischen und dynamischen Eigenschaften geprüft. Auf Grundlage der in diesen Prüfungen ermittelten Kennwerte konnte die Einsatzmöglichkeit dieser naturfaserverstärkten Thermoplaste für ein großflächiges Strukturbauteil gezeigt werden. Als Beispiel für ein solches Bauteil wurde ein 3,75 m langes Rotorblatt einer Windkraftanlage entworfen. Um eine Aussage über das Verhalten des Rotorblattes unter Belastung treffen zu können, wurden folgende Lastfälle mit Hilfe der FEM simuliert: - 50-Jahres-Böe, mit Windgeschwindigkeit von 50 m/s und stehendem Rotor - Nennlast, mit Windgeschwindigkeit von 11 m/s und drehendem Rotor Für die Bewertung des Verbundverhaltens wurde das Tsai-Wu-Ausfallkriterium herangezogen, da es eine Aussage über das Bruchverhalten von Faserverbunden unter mehrachsiger Belastung erlaubt. Die Auswertung dieser Simulationen ergab, dass es theoretisch möglich ist, naturfaserverstärkte Thermoplaste als Werkstoff in großflächigen Strukturbauteilen einzusetzen.

Gegenstand der Arbeit ist die Erarbeitung und Umsetzung eines reaktiven Aufbereitungsverfahrens im Doppelschneckenextruder zur kontinuierlichen Herstellung von gummimehlbasierten Elastomerlegierungen mit Polypropylenmatrix. Es wird eine Übersicht über den technischen Stand der Polymeraufbereitung in Doppelschneckenmaschinen sowie den Einsatz von Gummimehlen als funktionellem Füllstoff in Thermoplastmatrices gegeben, wobei neben verfahrenstechnischen Aspekten besonders auf die Möglichkeiten der Phasenkompatibilisierung in gummimehlhaltigen Polyolefincompounds zur Herstellung Thermoplastischer Elastomere eingegangen wird. Den Ausgangspunkt für die Verfahrensentwicklung bildet ein reaktiver Schmelzemischprozess in einem Innenmischer, auf dessen Basis die Auswahl der Rezepturkomponenten erfolgte. Gestützt auf eine Modellrezeptur erfolgte in diskontinuierlichen Voruntersuchungen im Labormesskneter eine Anpassung des Werkstoffsystems sowie die experimentelle Verifizierung möglicher Verfahrenskonzepte für die kontinuierliche reaktive Aufbereitung im Doppelschneckenextruder. Für die ausgewählten Verfahrenskonzepte wurden konkrete Extruderaufbauten konzipiert, deren stoff- und prozessgrößenabhängiges Betriebsverhalten auf Basis eines analytischen Prozessmodells abgeschätzt wurde. Nach vergleichenden experimentellen Untersuchungen der kontinuierlichen Verfahrensaufbauten, die auch Verweilzeitmessungen und Rezepturanpassungen einschlossen, wurde eine praxistaugliche Extruderkonfiguration ausgewählt und der Einfluss der technologischen Prozessgrößen auf die Werkstoffeigenschaften der Elastomerlegierungen untersucht. Mit optimierten Prozessparametern erfolgte die kontinuierliche reaktive Aufbereitung von Elastomerlegierungen mit variablen Gummimehlgehalten, deren Werkstoffverhalten umfassend charakterisiert wird / The present thesis deals with the development and implementation of a reactive compounding procedure in a co-rotating twin-screw extruder for the continuous preparation of ground rubber based Elastomeric Alloys with a polypropylene matrix. An overview about the state of the art of polymer compounding in twin-screw devices as well as of the utilisation of rubber powders as functional fillers in thermoplastic matrices is given. Beside process related aspects especially the methods of phase compatibilisation in ground rubber containing polyolefinic compounds for the preparation of Thermoplastic Elastomers are addressed. A reactive melt-mixing procedure in an internal mixer served as the base for the development of the continuous process as well as for the materials and formulations used. Preliminary experiments with a model formulation were carried out in a laboratory batch kneader to adapt the material system onto the requirements of the continuous process as well as to verify and select promising process concepts for the continuous reactive compounding in the twin-screw extruder. The selected concepts were transformed into extruder configurations followed by a simulation of their operating characteristics based on an analytical process model. The performance of the extruder configurations was verified by experiments that included also residence time investigations and further adaption of the formulation. The most suitable extruder setup was chosen for the investigation of the influence of the technological process parameters on the material properties of the Elastomeric Alloy model formulation. Using optimised technological parameters a familiy of Elastomeric Alloys with variable rubber powder content was prepared by continuous reactive compounding in the twin-screw extruder and followed by a comprehensive characterisation of their material performance and properties.

Introduction: Intrinsic and extrinsic urethral factors play a significant role in urinary continence mechanism in women. Urethral wall structure including inervation, perfusion of submucosal layer etc. is not clinically assessed despite its important role in urethral closure function. The association of incontinence and pelvic floor reconstructive surgery is well known. Every postoperative healing process is associated with factors of ischemia and neovascularisation. According those facts we would expect that the healing and scaring should involve intrinsic urethral mechanism. After reconstructive surgery Implants further increase scaring process. Methods: In our study we included patients with anterior compartment defect. We randomized patients into three interventional arms according the surgical approach and use of implants. Before and 3-5 month after the surgery we performed urodynamic studies and pelvic floor ultrasound examination, including Doppler for urethral perfusion assessment. Another early ultrasound scan was added forth day after surgery. We correlated ultrasound and urodynamic parameters. Results: We randomized 87 patients. We couldn't find any correlation between the morphologic changes and severity of incontinence. Methods for urethral perfusion assessment showed high inaccuracy...

The relationship between microstructure and mechanical properties of semicrystalline polymer materials has been a hot topic since many years in materials science and engineering. Isotactic polypropylene (iPP) is frequently used as a model material, due to its good mechanical properties and wide applications. In the past few years, numerous studies have been performed in the field of structural evolution during deformation. Previous results revealed that phase transition from crystal to mesophase happens in the crystal scale, lamellae orientation and fragmentation occurs in the lamellae scale, and even cavitation behavior exists in the larger scale. Although abundant work has been done, some problems remain under debate, for instance the relationship between lamellae deformation and cavitation behavior, the role of phase transition on the void formation, et al. In this study, well defined microstructure of iPP is obtained by annealing or adding nucleating agent. Afterward, the structural evolution under three types of mechanical load modes (including uniaxial stretching, creep, and stress relaxation) is in-situ monitored by synchrotron X-ray scattering. During uniaxial stretching, we revealed, for the first time, how lamellae deformation occurs in the time scales of elastic deformation, intra-lamellar slip, and melting-recrystallization, separated by three critical strains which were only rarely found to be influenced by annealing. Strain I (a Hencky strain value of 0.1) marks the end of elastic deformation and the onset of intra-lamellar slip. Strain II (a Hencky strain value of 0.45) signifies the start of the recrystallization process, from where the long period in the stretching direction begins to decrease from its maximum and the polymer chains in the crystal start to orient along the stretching direction. The energy required by melting arises from the friction between the fragmented lamellae. Strain III (a Hencky strain value of 0.95) denotes the end of the recrystallization process. Beyond the strain of 0.95, the long period and the crystal size remain nearly unchanged. During further stretching, the extension of the polymer chains anchored by lamellae triggers the strain hardening behavior. On the other hand, annealing significantly decreases the critical strain for voids formation and increases the voids number, but restricts the void size. For those samples annealed at a temperature lower than 90 oC, voids are formed between strain II and strain III. The voids are oriented in the stretching direction once they are formed. For those samples annealed at a temperature higher than 105 oC, voids are formed between strain I and strain II. The voids are initially oriented with their longitudinal axis perpendicular to the stretching direction and then transferred along stretching direction via voids coalescence. Additionally, the formation of voids influences neither the critical strains for lamellae deformation, nor the final long period, the orientation of polymer chains or the crystal size. β-iPP is a kind of metastable phase which can be induced only under special condition. By adjusting the morphology of N,N'-dicyclohexyl-2,6-naphthalene dicarboxamide (NJS) through self-assembly, the relative content of β-iPP (Kβ) is successfully controlled, under the condition that the weight content of NJS in the composite keeps at 0.3 wt. %. The microstructural evolution of the iPP/NJS composites with different Kβ during uniaxial stretching is studied. The results show that a higher Kβ could increase the number of the voids. However, the size of the voids is similar regardless of the NJS morphology. The β-α phase transition takes place after voids formation. During intralamellar and inter-lamellar slip, no obvious polymer chains orientation can be found for α-iPP. In the strain range of 0.1~0.6, the c-axis of the β-iPP crystal tends to orient perpendicular to the stretching direction due to lamellae twisting, which is a unique deformation mode of β-iPP lamellae. And the lamellae twisting are proposed to be responsible for the intense voids formation of the composite with higher Kβ. During creep, the evolution of the long period can be divided into four stages (primary creep, transition stage, secondary creep, and tertiary creep). This fits quite well with the macroscopic displacement and strain evolution. In primary creep, the long period along loading direction (L_p^∥) increases with time due to the stretching of amorphous phase, whereas the long period perpendicular to loading direction (L_p^⊥) decreases slightly. In secondary creep, strain increases linearly with time. Both L_p^∥ and L_p^⊥ exhibit the same tendency with strain. The increase of the long period is caused by lamellae thickening, which is a kind of cooperative motion of molecular chains with their neighbors onto the lamellae surface. The increasing rate of L_p^∥ is larger than that of L_p^⊥, indicating that the orientation of molecular chains along loading direction decreases the energy barrier for the cooperative motion. In tertiary creep, strain grows dramatically within a limited time. The lamellae are tilted and rotated, and then disaggregated. In addition, fibrillary structure is formed during lamellae breaking. The length of the fibrillary structure increases from 364 nm to 497 nm but its width stays at 102 nm as creep time increases. During stress relaxation, the local deformation behavior of the long period is affine with the macroscopic stress relaxation. However, the evolution of the crystal orientation and the void size lag behind the macroscopic stress relaxation. The decrease of the long period is mainly caused by the relaxation of the strained polymer chains in the amorphous phase. The retardation of the evolution of the crystal orientation is probably caused by the phase transition from stable α-iPP to metastable mesomorphic-iPP. By phase transition, the highly oriented α-iPP is transferred to weakly oriented mesomorphic-iPP. Due to the fact that the void is confined by the network of the strained polymer chains where lamellae blocks serve as the physical anchoring points, the phase transition contributes greatly to the viscoplastic deformation of the network. Consequently, the evolution of the voids size shows a similar trend with that of the phase transition. With this thesis, we gained a deeper insight into the relationship between structure and properties of semicrystalline polymers. The current study will not only benefit the understanding of polymer materials science but also serve as guidance for the processing of semicrystalline polymers for engineering applications.:1 Introduction 1 1.1 Isotactic polypropylene (iPP) 1 1.1.1 Chain structure of PP 1 1.1.2 Crystal forms of iPP 2 1.1.3 Lamellae of iPP 4 1.1.4 The morphology of the supra-structure of iPP 4 1.2 Structural evolution during deformation 5 1.2.1 Deformation process of semicrystalline polymers 5 1.2.2 Cavitation behavior of semicrystalline polymers 7 1.3 Synchrotron X-ray scattering 9 1.3.1 X-ray and its sources 9 1.3.2 The interaction between X-rays and objects 11 1.3.3 Wide angle X-ray scattering 12 1.3.4 Small angle X-ray scattering 13 2 Motivation and objectives 15 3 Samples preparation and basic characterization 17 3.1 Materials and samples preparation 17 3.1.1 Preparation of iPP films with single layer of spherulites and transcrystalline regions 17 3.1.2 Preparation of iPP plates crystallized with different thermal histories 17 3.1.3 Preparation of iPP/NJS plates with different morphologies of NJS 18 3.1.4 Preparation of microinjection molded iPP/NJS sample 18 3.2 Characterization 18 3.2.1 Differential scanning calorimetry (DSC) 18 3.2.2 Dynamic mechanical analysis (DMA) 19 3.2.3 Scanning electron microscopy (SEM) 19 3.2.4 Polarized optical microscopy (POM) 20 3.2.5 Rheology test 20 3.2.6 Gel Permeation Chromatography (GPC) 21 3.2.7 In situ synchrotron X-ray scattering measurements 21 3.2.8 X-ray scattering pattern processing and calculation 24 4 Microstructure characterization in a single iPP spherulite by synchrotron microfocus wide angle X-ray scattering 29 4.1 Introduction 30 4.2 The nucleation efficiency of the carbon fiber on iPP 31 4.3 Morphology of iPP spherulites and transcrystalline region 32 4.4 Defining of the position of the carbon fiber 33 4.5 Microstructure studies of the spherulite 34 4.5.1 Crystallinity in the spherulite 35 4.5.2 The ratio between “daughter” lamellae and “mother” lamellae in the spherulite 36 4.5.3 The orientation of the crystal axis in the spherulite 37 4.6 Conclusion 39 5 Influence of annealing on the mechanical αc-relaxation of iPP: a study from the intermediate phase perspective 41 5.1 Introduction 42 5.2 Crystal form of water cooled and annealed iPP 44 5.3 Microstructure of iPP with different thermal history 45 5.4 Melting behavior of iPP with different thermal history 50 5.5 Mechanical relaxation behavior of iPP with different thermal history 52 5.6 Conclusion 57 6 Critical strains for lamellae deformation and cavitation during uniaxial stretching of annealed iPP 59 6.1 Introduction 60 6.2 The true stress-strain curves of iPP uniaxial stretched at 75 oC 61 6.3 In Situ SAXS and WAXS Results 63 6.3.1 Synchronize mechanical test and in-situ SAXS/WAXS measurement 66 6.4 Lamellae deformation 67 6.4.1 The evolution of the long period 67 6.4.2 The evolution of the crystal size 69 6.4.3 The orientation of the c-axis of the crystal 71 6.4.4 The evolution of the crystallinity 72 6.5 Cavitation behavior 74 6.5.1 The onset strain of the voids formation and the voids direction transition 74 6.5.2 The evolution of the voids size 75 6.5.3 The scattering invariant (Q) of the voids 76 6.5.4 The morphology of voids 77 6.6 Final discussion 79 6.7 Conclusion 82 7 Accelerating shear-induced crystallization and enhancing crystal orientation of iPP by controlling the morphology of N,N'-dicyclohexyl-2,6-naphthalene dicarboxamide 83 7.1 Introduction 84 7.2 The self-assembly process of N,N'-dicyclohexyl-2,6-naphthalene dicarboxamide 85 7.3 Rheological behavior 88 7.3.1 Frequency sweep test 88 7.3.2 Strain sweep test 88 7.3.3 Steady-state shear test 89 7.4 Shear-induced crystallization 91 7.4.1 Crystallization kinetics studied by rheological method 91 7.4.2 In-situ SAXS measurement 93 7.4.3 Microstructure of iPP after shear-induced crystallization 96 7.4.4 The morphology of the sample 98 7.4.5 The crystallization mechanism 99 7.5 Conclusion 100 8 Influence of nucleating agent self-assembly on structural evolution of iPP during uniaxial stretching 101 8.1 Introduction 102 8.2 The morphology of the NJS in the compression molded iPP 103 8.3 Microstructure of iPP with different NJS morphologies 104 8.4 In-situ SAXS results 105 8.4.1 Cavitation behavior 107 8.4.2 Evolution of the long period 110 8.5 In-situ WAXS results 111 8.5.1 The β-α phase transition behavior 112 8.5.2 The orientation of the crystal 115 8.6 Conclusion 117 9 Microstructural evolution of iPP during creep: an in-situ study by synchrotron SAXS 119 9.1 Introduction 120 9.2 The creep curve 121 9.3 In-situ SAXS results 123 9.3.1 Evolution of long period and domain thickness 125 9.3.2 Lamellae tilting and rotation 128 9.3.3 Lamellae orientation and fibrillary structure formation 129 9.4 Conclusions 132 10 Microstructural evolution of iPP during stress relaxation 133 10.1 Introduction 134 10.1.1 The structural evolution during stress relaxation at 60 oC 135 10.1.2 The structural evolution during stress relaxation at 90 oC 140 10.2 Conclusion 145 11 Conclusion and outlook 146 12 References 148 13 Appendix 158 13.1 List of symbols and abbreviations 158 13.2 List of figures and tables 163 13.3 List of publications 171 14 Acknowledgements 173 15 Eidesstattliche Erklärung 175

Detta examensarbete är ett samarbete med Peab och deras dotterbolag Swerock. Idén som lagtgrunden till denna rapport är att undersöka vilken effekt inblandning av polypropylen har påtvå utvalda betongsammansättningar som används som anläggningsbetong med högexponeringsklass. De två utvalda betongsammansättningarna är dels en konventionellanläggningsbetong med hög exponeringsklass (benämns ”standardbetong” i denna studie) samten motsvarande variant med SweRocks nylanserande ”Eko-betong”. I eko-betongen har en delav cementen ersatts med masugnsslagg (restprodukt från stålindustrin) för att minimerautsläppen av koldioxid vid tillverkning av cementen. Syftet med detta examensarbete är attbehandla och undersöka huruvida inblandning av polypropylenfiber med olika doseringarpåverkar krympningen för anläggningsbetong. Målet med studien är att öka kunskapen omkrympning i anläggningsbetong. Frågeställningarna som beaktas i denna rapport innefattarsåledes hur de två specifika anläggningsbetongrecepten påverkas vid två olika doseringar avpolypropylen med avseende på krympning. Metoden för att kunna besvara frågeställningarnahar uteslutande varit insamling av empiri som i sin tur har möjliggjorts genom att gjutabetongprovkroppar av dessa två recept med olika doseringar av polypropylen. Totalt göts tolvstycken provkroppar fördelat på sex provkroppar per betongrecept. Vidare göts två provkropparper betongrecept och dosering av polypropylen. Provkropparna mättes och vägdes vid tiotillfällen under en period på ca 35 dagar och resultatet på krympningen för respektivebetongsammansättning blev ca: 1,3% utan polypropylen, 0,6% med normaldosering avpolypropylen och 1,4% för dubbelnormaldosering av polypropylen. Teoretiska värden påkrympningen för båda betongrecept beräknades fram med hjälp av modeller från Eurocode 2:Dimensionering av betongkonstruktioner och Betonghandboken: Material. De faktiska värdenasom mättes upp blev ca 20 gånger större än de teoretiska värdena för respektive betong.Viktiga felkällor som tas upp och behandlas i denna rapport är okontrollerade temperatur- ochfuktförhållanden vid förvaring av provkropparna, risken för felmätningar vid mättillfällena,varje provkropps unika betongsammansättning med mera. Betongsammansättningen i varjeenskild provkropp behandlas särskilt då en provkropp kan ha betydligt mer ballast(stenmaterial) än annan vilket i sin tur resulterar i en mindre uppmätt krympning. Därmedbedöms det att studien hade behövt ett större antal provkroppar av varje betongrecept för att påså sätt minska omfattningen av felkällor och erhålla ett mer tillförlitligt resultat. Dock visar deresultat som erhölls i denna studie på att polypropylen kan medföra en minskad krympning förde recept där polypropylen använts kontra de recept där polypropylen inte använts samt att ekobetongenkrymper generellt sätt mindre än standardbetongen. Dock går det inte att se någottydligt gemensamt samband mellan de två olika betongtyperna om huruvida en enkel- ellerdubbeldosering av polypropylen i betongen medför en mindre krympning än den andra utanendast att polypropylen medför en minskad krympning. Slutsatserna och svaren påfrågeställningarna blir således för denna studie är att inblandning av polypropylen medför engenerellt minskad krympning för båda anläggningsbetongrecepten men inget samband sompåvisar att dubbeldosering av polypropylen medför ytterligare krympningsminskning än vad ennormaldosering medför. / This thesis is a collaboration with Peab and their subsidiary Swerock. The idea behind thisreport is to investigate the effect of blending polypropylene on two selected concretecompositions used as construction concrete with a high exposure class. The two selectedconcrete compositions are partly a conventional construction concrete with a high exposureclass (referred to as "standard concrete" in this study) and a corresponding variant withSweRock's newly launched "Eko-betong". In eko-betong, part of the cement has been replacedwith blast furnace slag (residual product from the steel industry) to minimize carbon dioxideemissions during the production of the cement. The purpose of this thesis is to treat andinvestigate whether admixture of polypropylene fibers with different dosages affects theshrinkage of construction concrete. The aim of the study is to increase knowledge aboutshrinkage in fixed concrete. The issues considered in this report thus include how the twospecific construction concrete recipes are affected at two different dosages of polypropylenewith respect to shrinkage. The method for being able to answer the questions has exclusivelybeen the collection of empirical data, which in turn has been made possible by casting concretesamples of these two recipes with different dosages of polypropylene. A total of twelve testspecimens were cast, divided into six test specimens per concrete recipe. Furthermore, two testspecimens were cast per concrete recipe and dosage of polypropylene. The specimens weremeasured and weighed on ten occasions over a period of about 35 days and the result of theshrinkage for each concrete composition was about: 1.3% without polypropylene, 0.6% withnormal polypropylene dosing and 1.4% for double normal polypropylene dosing. Theoreticalvalues for the shrinkage for both concrete recipes were calculated using models from Eurocode2: Dimensioning of concrete structures and the Concrete Handbook: Materials. The actualvalues measured were about 20 times greater than the theoretical values for each concrete.Important sources of error that are addressed and treated in this report are uncontrolledtemperature and humidity conditions when storing the specimens, the risk of erroneousmeasurements at the time of measurement, the unique concrete composition of each specimenand more. The concrete composition in each individual specimen is treated especially as onespecimen may have significantly more aggregate (stone material) than another, which in turnresults in a less measured shrinkage. Thus, it is judged that the study would have needed a largernumber of specimens of each concrete recipe in order to reduce the extent of sources of errorand obtain a more reliable result. However, the results obtained in this study show thatpolypropylene can lead to a reduced shrinkage for the recipes where polypropylene has beenused versus the recipes where polypropylene has not been used and that the eco-concretegenerally shrinks less than the standard concrete. However, it is not possible to see any clearcommon connection between the two different types of concrete as to whether a single or doubledosing of polypropylene in the concrete causes a smaller shrinkage than the other, but only thatpolypropylene causes a reduced shrinkage. The conclusions and answers to the questions thusbecome for this study are that admixture of polypropylene entails a generally reduced shrinkagefor both fixed concrete recipes, but no connection that shows that double dosing ofpolypropylene entails further reduction of shrinkage than a normal dosing entails.