摘要：

In this Thesis, the potential use of vegetable oil-based monomers to prepare polyurethanes is highlighted. With a worldwide market of 14 millions tons/year, polyurethanes (PU)s are extremely versatile materials allowing a huge variety of applications in automotive, building and construction, flooring and packaging or in the medical field. They are synthesized from polyol and poly(isocyanate) reactants producing carbamate (urethane) bonds. It is worth noting that most of PUs come from the petroleum-based feedstocks, therefore, there is a growing interest in the use of natural reagents to replace petroleum based PUs. The preparation of PUs from renewable feedstock is currently receiving increasing attention in the industry and academia. In point of fact, there are more than 20 different polyols which are currently available commercially, and all of them coming from vegetable oils. For many high-tech applications PU materials should bear functionalities enabling tuning final material properties. The functionalization of PUs can be accomplished by introducing functional groups into oligodiols and further polymerization, post-polymerization modification, or by combining both strategies. Although the former approach is more experimentally feasible for the ease of incorporating functional groups into low or medium molecular weight oligodiol, in practice the functionalization is achieved by a variety of methods including the synthesis of polyols bearing reactive pendant groups to prepare novel comb-type, grafted structural functional polymers through post-modification. So far, there have been a few reports focusing on the preparation of novel functional bio-based PUs bearing reactive pendant groups.Over the past few years, several approaches have been used to enhance the properties of PUs, in this way the synthesis of supramolecular PUs (SPUs) can receive relevant attention. These reversible behaviours endow supramolecular systems with versatile functions, such as facile processing/recycling, self-healing, shape memory and high stimuli-response. Several features make supramolecular chemistry particularly attractive when comes to self-healing: reversibility and speed, directionality, and sensitivity. In contrast to covalent bonding, these networks can be remodelled rapidly and reversibly form from fluid-like to solid-like states. The possibility to repeatedly conduct the healing process even after multiple damages have occurred is the most important benefit of supramolecular self-healing materials. Supramolecular shape-memory PUs based on thermal-reversible non-covalent bonding recently have been another new kind of shape-memory polymers. In these systems, the reversible non-covalent interactions are used to stabilize mechanically strain stated in polymer elastomers; and shape recovery is achieved upon heating due to the dissociation of non-covalent bonds. After observed the previous work reported, the specific objectives of this Thesis are: - To prepare renewable monomers from castor oil derivatives containing different side-chain functional groups inert in front to diisocyanate group. - To develop new side-chain functionalized PUs with isophorone (IPDI) and hexamethylene diisocyanate (HDI) respectively. - To carry out the post-polymerization modification in mild conditions by using thiol-ene/yne coupling reactions. - To prepare a family of side-chain SPUs using a PU which contains tertiary amine as pendant group and carboxylic acids. - To combine the post-polymerization modification by photoinitiation thiol-ene/yne coupling reactions and supramolecular chemistry to synthetize SPU networks - To analyse the new acquired properties of the modified PUs. This Thesis is addressed to the development of side-chain functionalized polyurethanes (FPUs), with enhanced properties, made from fatty acid-based functional diols and two different diisocyanates; isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI). The novel FPUs present tertiary amine and alkyl, allyl, propargyl moieties or the combination of these, as side-chain

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