The purpose of the work is the determination of flexural properties for thebiocomposite Durapulp. The study includes laborative tests on Durapulp andreference materials, commonly used in the building sector. Stiffness and strength of Durapulp show that it has the potential as a replacement for conventional wood-based materials.

The work focuses on new processes for the preparation of lactic acid derivatives. The main objective was to verify the feasibility of preparing high molecular weight polylactide using ethyl lactate as a precursor of lactide synthesis. Part of the work is devoted to the new ethyl lactate synthesis method. The experimental part of the thesis is divided into partial key steps on the way from the lactic acid to the high molecular polylactide. The preparation of anhydrous ethyl ester of lactic acid (EtLA) was solved in an innovative way using alcoholysis of the oligomeric lactic acid. A kinetic model for isothermal alcoholysis and equimolar reactants ratio was derived from this method. The ethyl lactate was oligomerized by transesterification into the low and high molecular weight oligomer with the help of newly found catalysts suitable for the reaction medium. Stannous lactate was used as catalyst for oligomerization of the low molecular weight polymer suitable for the preparation of lactide (Mn 1000 g.mol-1). Experimental polymerization of ethyl lactate into high molecular weight product in tens of kDa has been investigated with newly synthesized tetraethyllactoyl titanate, Ti(EtLA)4. The laboratory method was derived for the depolymerization of the oligomer into lactide. Optimal conditions found for lactidation are as follow: temperature 225 ° C, pressure 2 kPa, catalysis 0,05 mol% of stannous lactate (with respect to oligomer lactate units). The prepared lactide was refined to polymer grade purity by distillation and subsequent recrystallization from ethyl acetate and toluene. The method for the preparation of high molecular weight PLA through ROP polymerization of lactide has been optimized. By optimization, suitable catalyst concentration was found in combination with the polymerization temperature and the polymerization length. An equimolar mixture of Tin 2-ethylhexanoate and 1-decanol was used as the catalytic system. The optimal ROP conditions for achieving the maximum molecular weight and suppressed polymer coloration (yellowing) are: catalyst concentration 0,01 mol%, temperature 160 °C, and polymerization length 4 hours. PLA with molecular weight Mw= 447 ± 7,8 kg.mol-1 was prepared at these conditions and good repeatability of the result was achieved. The effect of naturally occurring lactide contaminants and their influence on the course and ROP result was experimentally verified on the optimized polymerization system. The purpose was to explore the effect of lactide contamination with water and ethanol as natural lactide contaminants. The results clearly confirm the orderly lower sensitivity of the polymerization system for the presence of ethanol as compared to water contamination. In the case of the presence of water, the course and the result of the polymerization in terms of both the conversion and achieved molecular weights are negatively affected, even when the water content is in the order of 0,001%. Conversely, the presence of ethanol has a positive effect on lactide conversion and polymer polydispersity. Lactides with an alcohol content of about one-tenth of a percent are suitable to reach molecular weights of PLA similar to commercially available products. This difference shoves a significant advantage in the proposed technology of preparing PLA from ethyl lactate, especially for easier purification of crude lactide into polymer grade purity.

This thesis deals with 3D printing, materials used for 3D printing, testing of the materials and learning their real parameters. Goal of the thesis is comparing selected materials, executing series of mechanical test and selecting suitable material for printing high-quality plastic parts for use in automobiles, especially for reproduction of parts that are no longer made for oldtimers and for use in motorsport.

This diploma thesis deals with use of lactic acid esters for preparation of lactides and PLA. In the theoretical part, it has been processed literature review focus on manufacturing technologies and properties of lactic acid and its esters (especially ethyl ester and lactides). In the experimental part, it has been designed and realized functional laboratory apparatus for preparation of cyclic dimer of lactic acid – lactides. On this apparatus, there were carried out principal laboratory experiments leading to optimization of lactides yields using various catalysts.

This diploma thesis solves the 3D printing problematics for non-commercial printers. Firstly possibilities of its using, heat diffusion and printing materials are described. Next part of thesis is focused on heating pads and printing nozzles for which 3D models in SolidWorks software are created. The temperature analyzes are tested with these models and then comparing of results is done. Working models for SolidWorks Plastics and SolidWorks Simulation software is created in following part. Thanks to this software tools printing model is simulated and deformation creating in printing process is observed. The most suitable solutions are chosen from gained solutions.

Ein Bio-PE und ein PLA werden mit einem für Gleitanwendungen üblichen PE-UHMW tribologisch verglichen. Den beiden Werkstoffen werden zusätzlich die Naturstoffe Haferspelzen, Hanfschäbengranulat und Buchefasern mit einem Füllstoffgehalt von 30 Gew.% zugesetzt. Diese Naturstoffe sind teilweise Reststoffe aus der verarbeitenden Industrie und können bei guten Ergebnissen nachhaltig wiederverwendet werden. Durch tribologische Untersuchungen dieser Compounds soll ein zweckmäßiger und nutzbringender Einsatz der Naturstoffe aufgezeigt werden.

Rapporten avser ett produktutvecklingsprojekt hos ett företag. Företaget har ett problem avseende kontaktering i deras handhållna batteridrivna produkter, problemet har varit aktuellt att lösa under längre tid. Problemet yttrar sig i form av diverse olika tekniska, elrelaterade, sporadiska fel till följd av tillverkningsteknikens begränsningar i form av toleranssättning. När fullgod kontaktering (fullständigt hoptryckta kontaktdon) inte uppnås resulterar det också i att batteriet inte sitter helt inspänt och konstruktionen upplevs som racklig vilket minskar kvalitetsintrycket av produkten i sin helhet. Företaget kan, med modern tillverkningsteknik, inte garantera att batteriet placeras in i deras produkter på ett sätt som leder till fullgod kontaktering. Eftersom nolltolerans för variation i distanser och geometrier från produktion inte är realistiskt behöver företaget en ny konceptinriktning som tillåter normala avvikelser utan att skapa elektriska problem. Projektet har haft snäva ramar, krav och avgränsningar som har krävt en metodisk produktutvecklingsprocess. Kravbilden innefattar total kompabilitet med samtliga batterier i produktsortimentet, kontaktering med nolldistans i gränssnittet mellan produkt och batteri samt potential för fullständig universalitet i företagets olika produkter. Lösningen får dessutom inte öka komponentantalet eller monteringstiden avsevärt. Lösningen som tagits fram klarar variationer i distanser upp till fem millimeter och tillåter en svarande linjär rörelse i samband med placering av batteri. Oavsett vilka distanser, från det produktions tolererade intervallet, som en given produkt besitter uppnås fullgod kontaktering och batteriet spänns fast vilket minskar spel i placering av batteriet och ökar kvalitetsintrycket. Projektets ramar ledde till en lösning som både är kompakt och kan platsa i hela det handhållna sortimentet och som är fullständigt universell. Företaget har visat stort intresse för lösningen som anses besitta potential och lösningen kan komma att implementeras i företagets produktsortiment. / This paper describes a product development project at a company. The company has a technical issue regarding connection between the battery and a given unit in their handheld electrical range of products. The problem consists of a range of sporadic, technical electrical issues because of the inherent limitations of the manufacturing processes due to tolerance of variations in the produced units and it has been relevant to solve for some time. When the connection between a product and its battery isn’t apposite it results in a rattling battery which makes for a less appealing product. Modern methods of manufacturing don’t allow zero tolerance for variation from production and so, the company needs a new direction that allows for normal variations without them causing various electrical issues. The project has been affected by strict requirements and demarcations that have made for a strict, methodical product development approach.The requirements consist of an absolute compatibility with the range of batteries used with the Company’s handheld electrical products, connection with a zero-tolerance distance in the interface between the product and the battery and the potential for universal implementation in the Company’s various products. The resulting system is also not allowed to increase the number of components, or the time spent assembling the units in a substantial way. The resulting system developed can accommodate variations of a magnitude of five millimetres and allows a responsive linear movement when a battery is placed in its socket. Regardless of the magnitude of tolerated variations from production, the solution allows for a zero-distance connection in the interface between the battery and the unit. The system also holds the battery in place which diminishes the battery rattling and improves the impression of the products quality. The framework of the project led to a solution that can fit in the entire handheld product range meaning the solution is fully universal. The company has shown interest for the system and considers it to have potential for future implementation.

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The use of plastic has increased markedly in recent years which has led to more fossil fuels being used and more plastic in nature. This is a literature study that researches on how bio- based plastics can be used instead of plastics made from fossil fuels. The report is written in collaboration with Biotage, which is a global impact tech company that wants to use plastic parts that are made of more sustainable plastic for their products. Relevant and contemporary literature is reviewed, and several alternatives are addressed. The mechanical and physical properties of the different plastics are compared. Laboratory tests are performed on bio-based polyethylene, poly (lactic acid), bio-based polypropylene, polypropylene that contains wood fibre, recycled polypropylene and fossil-based polypropylene that is currently used by Biotage. The properties and way of manufacturing the plastics is discussed according to environmental aspects, as well as cost and recycling. This leads to the result that different plastics can be used for the different parts but plastics produced from bioethanol or biomass would be a more sustainable choice than plastic from fossil fuel.