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Rigid polyurethane and polyisocyanurate (PUR-PIR) foams are one of the most effective thermal insulation materials applied in a wide range of industries. A sustainable solution for the production of these materials is to substitute one of their petrochemical components with a component produced from bio-based resources, like vegetable oils. The biggest disadvantage of this type of thermal insulation is its high flammability which usually is reduced by an addition of halogen-based flame retardants. Halogenated flame retardants are getting out of use due to potential health risks. Two different bio-based polyols obtained from rapeseed oil were applied to develop rigid PUR-PIR foams with isocyanate indices of 150 and 250. Flammability of these materials was decreased using an intumescent expandable graphite (EG) filler; 0%; 3%; 6% and 9% contents of EG were used. Flammability (Cone calorimeter), combustion (limited oxygen index, thermal imaging), thermal stability (TGA/DTG) were studied for the developed PUR-PIR foams. The addition of EG did not change the ignition behaviour of the developed materials but it had a significant influence on other flammability properties. Due to the development of a stable char layer, the peak value of the heat release in the Cone Calorimeter test was reduced from 240 to 136 kW/m 2 , the released smoke was also reduced from 560 to 288 m 2 /m 2 . TGA graphs showed a significant char formation (sample with 9% of EG) that was stable at high temperatures, over 400 °C. The addition of EG to the PUR-PIR system had a positive effect on the burning process which was confirmed by thermal imaging camera results. The formation of the char layer moderated the combustion of the PUR-PIR foams and increased the burning time. [ABSTRACT FROM AUTHOR]

This study presents the development and analysis of rigid polyurethane-polyisocyanurate (PU-PIR) foam synthesized from high functionality tall oil (TO) based polyols. Three PU-PIR formulations with varied high functionality TO based polyol content (45, 75 and 95 pbw) and a different tier of isocyanate (NCO) indexes (110, 150, 200, 300 and 400) for each formulation were compared to a formulation developed using conventional raw materials, mainly obtained from petrochemicals. Using the Fourier transform infrared spectral analysis (FTIR), the chemical structure of the foams was evaluated with emphasis on the characteristic PU-PIR signal ratio and isocyanurate signal peaks. The thermal properties of the PU-PIR polymer matrix were characterized using the thermogravimetric analysis (TGA) method by comparing the thermal degradation temperatures at 5%, 25% and 50% and residual masses. Technological parameters and thermal degradation results indicate that TO is a suitable renewable resource for polyol in a rigid PU-PIR foam formulation, but the results from FTIR analysis suggest that a small optimization in the foam developing process is necessary due to an increasing amount of unreacted NCO groups in samples with the NCO index above 200. • TO polyol gives the foam a renewable material content up to almost 25% of the mass. • TO polyol ensures an improved thermal degradation stability in rigid PU-PIR foams. • The developed formulation is well-suited for rigid PU and rigid PIR foam both. [ABSTRACT FROM AUTHOR]

Rapeseed is currently cultivated as an industrial crop in Latvia as a source of oil rich biomass to contribute to renewable energy goals of the European Union. However, rapeseed oil can also be used as a feedstock biobased polyurethane production. Latvian State Institute of Wood Chemistry have developed polyols based on rapeseed oil and have developed biobased and volatile organic compounds-free polyurethane coatings. The main aim of this study was to present a Life Cycle Inventory of spring and winter rapeseed produced in Northern European country Latvia based on primary data of agricultural practices used in this region. The study was carried in accordance with ISO 14040 and ISO 14044. Data were collected from a large crop company in Latvia to ensure a specific and accurate data collection for the definition of the complete supply chain. The reference unit of this study was defined as 1 ha, time horizon 2008–2016, stages from the raw materials production to the seed harvesting were considered. The data presented will add to and expand the existing knowledge of rapeseed production in other European countries. Lastly, this paper is the first in a series of papers that will result in a complete Life Cycle Assessment for these develop polyurethane coatings based on rapeseed oil polyols to avoid black box unit process and provide transparent results. [ABSTRACT FROM AUTHOR]

Porous polyurethane-polyisocyanurate (PUR-PIR) composites have been synthesized using two types of rapeseed oil-based bio-polyols. The bio-polyols from rapeseed oil were synthesized using two methods: (i) transesterification and (ii) epoxidation followed by oxirane ring opening. The PUR-PIR porous materials were prepared with two isocyanate indices, 150 and 250, and were modified with carbon fibres (CF) in an amount of 3 and 6 wt% of the total foam mass. The structure of the composites was examined using scanning electron microscopy. Thermal and mechanical properties of the composites were determined through a thermogravimetric analysis and measurements of the thermal conductivity, compressive strength, and Young modulus. The influence of CF on the composite flammability was analyzed using oxygen index and cone calorimeter tests. The investigations of the mechanical properties have shown that the compressive strength is the most beneficial in the case of the PUR-PIR foams modified with 6 wt % of CF. The studies have shown that the oxygen index of the composites increases with an increasing CF content and isocyanate index. An addition of CF reduces the heat rate release, especially for the materials with an isocyanate index of 250. An introduction of CF into the PUR-PIR foam structure is a way to improve the thermal stability and to decrease the flammability of final porous composites. [ABSTRACT FROM AUTHOR]

As part of this work, the test results for ureaurethane elastomers (PUURs) manufactured with the use of tall oil (TO)-based polyols with a rosin acid content ranging from 2 to 20% are presented. The goal of this study was to verify the thermal and mechanical properties of bio-based PUURs. The physicomechanical properties of PUURs were tested along with the strength (static tensile test) and thermal properties: thermogravimetry (TGA), differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). A structural analysis of the materials was also carried out via Fourier transform infrared (FTIR) spectroscopy. The replacement of the chain extender with tall oil-based polyols resulted in materials with different properties, different chemical constitutions and different thermal decomposition patterns. PUURs with TO polyols had a higher thermal resistance, and this resistance increased for higher isocyanate numbers ( I NCO ). The thermal decomposition of the tested PUURs with TO polyols increased with the increase in the rosin acid content. The mechanical properties of the PUURs show that changing the chain extender with the TO polyols causes an increase in the storage modulus. [ABSTRACT FROM AUTHOR]

Abstract A second generation renewable raw material – tall oil, which is a by-product of the cellulose pulping, was valorised for polyol precursor synthesis. Tall oil fatty acids were epoxidized by in-situ generation of peroxy carboxylic acids in presence of immobilized lipase catalyst – Novozym® 435. The described epoxidation was carried out at milder conditions (40 °C) than typical epoxidation. No organic solvents and no additional carboxylic acids were used for proposed process. Relatively high yields of epoxide oxygen content were achieved (i.e. 4.49–6.00%). The influence of molar ratios between ethylenic unsaturation and hydrogen peroxide (1.0/1.0–1.2), Novozym® 435 catalyst content (1.5–4.5%) and hydrogen peroxide concentration (15–35%) on the epoxidation process were investigated. The epoxidation process was monitored by the change of the relative oxirane conversion and ethylenic unsaturation. The change of the chemical structure of the epoxidized tall oil was investigated using FTIR spectroscopy. Graphical abstract Image 1 Highlights • Tall oil fatty acids were used for polyol precursor synthesis. • Peroxy carboxylic acids were generated in-situ. • Epoxidation was done in presence of immobilized lipase catalyst Novozym 435. • Lipase based biocatalyst allowed to develop milder epoxidation process. • No organic solvents and additional carboxylic acids were used for the epoxidation. [ABSTRACT FROM AUTHOR]

This work presents the results in the field of materials engineering, and they are related to recycling of paper production waste sludge particles at amounts of 10 wt% and 20 wt% in tall oil polyol-based rigid polyurethane foam with and without tris (1-chloro 2-propyl) phosphate flame retardant. The impact of both systems on physical and mechanical properties, thermal stability, fire resistance and ignitability is studied. Paper production waste sludge particles filled rigid polyurethane foams display better fire performance thus resulting into reduction of the emission of CO 2 and CO as well as reduction in average heat release rate. Scanning electron microscopy has shown that paper waste sludge particles and tris (1-chloro 2-propyl) phosphate together act systematically, and synergism between two materials may be observed. It is as well determined that paper production waste sludge particles reduce thermal conductivity by approx. 15% for polyurethane foam with paper production waste sludge particles and by approx. 13% for polyurethane foam with paper production waste sludge particles and conventional flame retardant. Moreover, the substitution of tris (1-chloro 2-propyl) phosphate, petroleum based polyol and hydroflurocarbons with 10 wt% and 20 wt% of PPWS particles, tall oil polyol and water reduces carbon dioxide emission by 60.8% and 39.6%, respectively, contributing to cleaner production of rigid polyurethane foam. [ABSTRACT FROM AUTHOR]

This study is an investigation of the suitability of the thermogravimetry and differential thermal analysis method coupled with Fourier Transform Infrared spectrometry (TG/DTA-FTIR) for a thermal degradation gaseous product analysis of a rigid polyurethane-polyisocyanurate (PU-PIR) foam synthesised from high functionality tall oil fatty acids (TOFA) based polyols. The FTIR spectra of the TG-generated gaseous thermal degradation products of three PU-PIR formulations with varied high functionality TO based polyol content (45, 75 and 95 pbw) and a different tier of isocyanate (NCO) indexes (110, 150, 200, 300 and 400) for each formulation were compared to the spectra of a formulation developed using conventional raw materials. The chemical bands of known chemical compounds and unknown compounds containing specific groups for the foams were evaluated; the focus was on the maximum release rate for specific chemical compounds (CO 2 ; –NCO; H 2 O; C O) to determine the temperature zone values of the main thermal degradation phases. The experiments were carried out at a low oxygen environment, providing valuable data on the trends for the excretion of specific gaseous substances from the rigid PU-PUR foam that could be released in a real fire, where organic building materials that possess a porous matrix might be present and the nature of the combustion process is predominantly heterogeneous oxidation. • TG/DTA-FTIR method is suitable for qualitative PU smoke analysis. • Tall oil fatty acid (TOFA)- based polyol prolongs smouldering process. • TOFA-rich formulations can generate a greater output of CO 2 , CO and water steam. • All formulations have three distinct thermal degradation phases. [ABSTRACT FROM AUTHOR]

Vegetable oils offer a reliable chemical platform to synthesize polyols for polyurethane production to replace fully or partially polyurethane precursors that are derived from petrochemical resources. Rapeseed, a renewable feedstock widely available in Northern Europe, was used as a bio-based feedstock. In the present study, a cradle-to-gate Life Cycle Assessment for a pilot scale bio-based polyol production was carried out. Life Cycle Inventories were built on up-to-date regionalized inventory for rapeseed production and experimental data for polyol synthesis were obtained from a pilot scale (50 L) reactor. Bio-based polyols were compared with the petrochemical counterpart. Life Cycle Assessment was performed using SimaPro 9.0 and impacts were evaluated with ReCiPe Endpoint and Midpoint methods and Cumulative Energy Demand. The two developed rapeseed oil based polyols were analyzed with three different modelling approaches for the bio-based feedstock stage – system expansion, mass allocation and economic allocation. The results indicate that, compared to petrochemical polyols in all cases of allocation bio-based rapeseed oil polyols have a better environmental performance in 8 out of the 18 ReCiPe midpoint impact categories and lower Cumulative Energy Demand. However, results also showed that the choice of allocation in the bio-based feedstock production stage has a significant impact on the results. Image 1 • Cradle-to-gate LCA has given complex answers that are not unidirectional. • Rapeseed oil is a major contributor to the environmental load of biobased polyols. • Polyols evaluated with three different allocations for bio-based feedstock stage. • Allocation method in bio-based feedstock production stage has a strong influence on the results. • Possible to achieve GHG emissions reduction of 1.4–3.0 kg CO 2 -eq.per kg polyol. [ABSTRACT FROM AUTHOR]