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Faraday tomography of a field centred on the extragalactic point source 3C 196 with the LOw Frequency ARray (LOFAR) revealed an intertwined structure of diffuse polarised emission with straight depolarisation canals and tracers of the magnetized and multi-phase interstellar medium (ISM), such as dust and line emission from atomic hydrogen (HI). This study aims at extending the multi-tracer analysis of LOFAR data to three additional fields in the surroundings of the 3C 196 field. For the first time, we study the three-dimensional structure of the LOFAR emission by determining the distance to the depolarisation canals. We use the Rolling Hough Transform to compare the orientation of the depolarisation canals with that of the filamentary structure seen in HI and, based on starlight and dust polarisation data, with that of the plane-of-the-sky magnetic field. Stellar parallaxes from $Gaia$ complement the starlight polarisation with the corresponding distances. Faraday tomography of the three fields shows a rich network of diffuse polarised emission at Faraday depths between $-10~{\rm rad~m^{-2}}$ and $+15~{\rm rad~m^{-2}}$. A complex system of straight depolarisation canals resembles that of the 3C 196 field. The depolarisation canals align both with the HI filaments and with the magnetic field probed by dust. The observed alignment suggests that an ordered magnetic field organises the multiphase ISM over a large area ($\sim$20$^{\circ}$). In one field, two groups of stars at distances below and above 200 pc, respectively, show distinct magnetic-field orientations. These are both comparable with the orientations of the depolarisation canals in the same field. We conclude that the depolarisation canals likely trace the same change of the magnetic field as probed by the stars, which corresponds to the edge of the Local Bubble., Comment: 14 pages, 11 figures, accepted for publication in A&A

Observations of synchrotron emission at low radio frequencies reveal a labyrinth of polarised Galactic structures. However, the explanation for the wealth of structures remains uncertain due to the complex interactions between the interstellar medium and the magnetic field. A multi-tracer approach to the analysis of large sky areas is needed. This paper aims to use polarimetric images from the LOFAR Two metre Sky Survey (LoTSS) to produce the biggest mosaic of polarised emission in the northern sky at low radio frequencies (150 MHz) to date. The large area this mosaic covers allows for detailed morphological and statistical studies of polarised structures in the high-latitude outer Galaxy, including the well-known Loop III region. We produced a 3100 square degree Faraday tomographic cube using a rotation measure synthesis tool. We calculated the statistical moments of Faraday spectra and compared them with data sets at higher frequencies (1.4 GHz) and with a map of a rotation measure derived from extragalactic sources. The mosaic is dominated by polarised emission connected to Loop III. Additionally, the mosaic reveals an abundance of other morphological structures, mainly {narrow and extended} depolarisation canals, which are found to be ubiquitous. We find a correlation between the map of an extragalactic rotation measure and the LoTSS first Faraday moment image. The ratio of the two deviates from a simple model of a Burn slab (Burn 1966) along the line of sight, which highlights the high level of complexity in the magnetoionic medium that can be studied at these frequencies., 20 pages, 25 figures, accepted for publication in A&A

Faraday tomography of radio polarimetric data below 200 MHz from LOFAR are providing us with a new perspective on the diffuse and magnetized interstellar medium (ISM). Of particular interest is the discovery of Faraday-rotated synchrotron polarization associated with neutral gas, as traced by atomic hydrogen (HI) and dust. Here we present the first in-depth numerical study of these LOFAR results. We produce and analyze comprehensive synthetic observations of low-frequency synchrotron polarization from MHD simulations of colliding super shells in the multiphase ISM. We define five distinct gas phases over more than four orders of magnitude in gas temperature and density, ranging from hot, and warm, fully ionized gas to cold neutral medium. We focus on the contribution of each gas phase to synthetic observations of both rotation measure and synchrotron polarized intensity below 200 MHz. We also investigate the link between the latter and synthetic observations of optically thin HI gas. We find that, not only the fully ionized gas but also the warm partially ionized and neutral phases strongly contribute to the total rotation measure and polarized intensity. However, the contribution of each phase to the observables strongly depends on the choice of integration axis and the orientation of the mean magnetic field with respect to the shell-collision axis. Strong correlation between HI synthetic data and synchrotron polarized intensity, reminiscent of LOFAR results, is obtained with lines of sight perpendicular to the mean magnetic field direction. Our study suggests that multiphase modelling of MHD processes is needed in order to interpret observations of the radio sky at low frequency. This work is a first step toward understanding the complexity of low-frequency synchrotron emission that will be soon revolutionized by large-scale surveys with LOFAR and the SKA., Comment: 17 pages, 20 figures, accepted by A&A, in press

N‐tert‐butylacrylamide (NtBA) was copolymerized with ethylene glycol dimethacrylate (EDMA) in butanone solution over a wide composition and conversion range, using dibenzoyl peroxide (Bz2O2) as a free‐radical initiator. The copolymer composition was determined from the nitrogen content. Using only low conversion (≤20%) collected for the copolymerization reactions, monomer reactivity ratios were estimated using the Kelen‐Tudos graphical method and were found to be r1=0.26 (NtBA) and r2=7.05 (EDMA). In order to get a better insight into the mechanism of nanoporous copolymers of NtBA with EDMA preparation by thermal degradation of copolymers of N‐acryl‐N,N′‐di‐tert‐butylurea (A‐DitBuU) with EDMA, nonporous copolymers (model compound), of the same chemical structure and composition, were prepared by performing copolymerization of NtBA with EDMA up to the high conversion of 97–100%. Thermal behavior of nanoporous and nonporous copolymers of NtBA with EDMA was studied.

Synthesis and free‐radical initiated copolymerization of N‐acryl‐N,N′‐di‐tert‐butylurea (A‐DitBuU) with ethylene glycol dimethacrylate (EDMA) are described. The A‐DitBuU monomer was prepared by the condensation of acrylic acid to the N,N′‐di‐tert‐butylcarbodiimide (DitBuC) at room temperature. Copolymers of A‐DitBuU with EDMA of different monomer to monomer ratios in the feed were prepared in the presence of dibenzoyl peroxide (Bz2O2) in butanone at 70°C for 48 h up to a high conversion. The obtained crosslinked copolymers are insoluble in organic solvents. Copolymers thermal decomposition resulted in separation of tert‐butylisocyanate (C4H9NCO) in the temperature range between 180 and 280°C and by the formation of the thermally stable molecularly imprinted copolymers of N‐acryl‐N‐terc‐butylamide (A‐tBuA) with EDMA.

Copolymers of methacryl‐N,N′‐diisopropylurea (MA‐DiPrU) with ethylene glycol dimethacrylate (EDMA) at monomer‐to‐monomer ratios in the feed: 0.3/0.7; 0.5/0.5; 0.7/0.3; 0.8/0.2 were prepared in butanone in the presence of 2% of dibenzoyl peroxide (Bz2O2) at 70°C for 48 hr. Copolymers regardless of the ratio of comonomers in the feed decompose thermally at 200–250°C under the separation of isopropylisocyanate (iPrNCO). Residues after the removal of iPrNCO are thermally stable nanoporous crosslinked copolymers of methacryl‐isopropylamide (MA‐iPrA) with EDMA which decompose by a one‐step mechanism between 280°C and 450°C. Nonporous model copolymers poly(MA‐iPrA‐co‐EDMA) of similar composition, prepared by copolymerization of MA‐iPrA with EDMA, also decomposed by a one‐step mechanism as shown by TGA measurements.

Copolymers of methacryl‐dicyclohexylurea (MA‐DCU) with ethylene glycol dimethacrylate (EDMA) at monomer‐to‐monomer ratios in the feed: 0.3/0.7, 0.5/0.5, 0.7/0.3, 0.8/0.2 were prepared in butanone in the presence of 2% of dibenzoyl peroxide at 70°C for 48 hr. Copolymers, regardless of the ratio of comonomers in the feed, decompose thermally at 200–250°C under the separation of cyclohexylisocyanate (C6H11NCO). Residues after the removal of C6H11NCO are thermally stable nanoporous crosslinked copolymers of methacryl‐cyclohexylamide (MA‐CHA) with EDMA, which decompose by a one‐step mechanism between 300°C and 480°C.

Copolymerization of N-acryl-N,N′-dicyclohexylurea with ethylene glycol dimethacrylate or divinyl benzene in the presence of dibenzoyl peroxide as initiator gave corresponding crosslinked copolymers. Both copolymers thermally decompose by two-step mechanism. The first step separates cyclohexylisocyanate, thus forming the thermostable residue, which contains molecular imprints of cyclohexylisocyanates.

INA kao distributer motornih goriva ima obavezu staviti na hrvatsko tržište određeni udio energije iz biogoriva u skladu sa Zakonom o tržištu biogoriva u cestovnom tranportu i prijevozu. Ina je kao biokomponentu 2011. godine počela koristiti metilne estere masnih kiselina (eng. fatty acid methyl esters, FAME). Značajan porast udjela energije iz biogoriva, tj. udjela biokomponente u sljedećim godinama zahtijeva uvođenje novih tipova biokomponenti pogodnih za korištenje u Ininim rafinerijama. Hidoobrađeno biljno ulje (eng. hydrotreated vegetable oil, HVO), jedno je od bioobnovljivih sintetičkih goriva, zvanih eng. drop-in fuel. Hidrogenirano biljno ulje koristi se kao visokokvalitetna komponenta za namješavanje dizelskog goriva ili kao standardno dizelsko gorivo. Vrlo je slično sintetičkom dizelskom gorivu dobivenom tehnologijama „plin u kapljevinu“ (eng. gas to liquid, GTL) i „biomasa u kapljevinu“ (eng. biomass to liquid, BTL). Korištenjem hidrogeniranog biljnog ulja dobivaju se bolje performanse vozila i manje emisije u odnosu na konvencionalno dizelsko gorivo. Hidroobrađeno biljno ulje praktički je gorivo bez sumpora i bez aromatskih ugljikovodika s visokim cetanskim brojem. Zbog tih karakteristika po kvaliteti superioran je u odnosu na konvencionalno dizelsko gorivo i FAME. Jedno od interesantnih svojstava je i njegova niska gustoća u odnosu na dizelsko gorivo. Ovo svojstvo izuzetno je zanimljivo za Inu radi povremene prerade nafta iz zapadno-afričkih zemalja koje karakterizira visoka gustoća plinskih ulja. Korištenje FAME kao biokomponente u dizelskom gorivu dodatno povećava gustoću dizelskog goriva. U radu je ispitana mogućnost namješavanja HVO kao biokomponente u dizelsko gorivo i mješavinu dizelskog goriva i FAME radi zadovoljenja HRN EN 590 norme za dizelsko gorivo. Također je ispitan utjecaj dodatka hidroobrađenog biljnog ulja na značajna svojstva dizelskog goriva. Maksimalna količina hidroobrađenog biljnog ulja namiješana u dizelsko gorivo ovisi o gustoći goriva. U ispitano dizelsko gorivo dodano je 18 % v/v što je maksimalna količina hidroobrađenog biljnog ulja da se zadovolji EN 590 norma u odnosu na propisanu gustoću. U mješavinama dizelskog goriva s dodatkom hidrogeniranog biljnog ulja zabilježeno je smanjenje gustoće i značajan porast cetanskog broja. U mješavini hidro-obrađenog biljnog ulja s dizelskim gorivom i FAME zabilježena je ista gustoća koju ima početno dizelsko gorivo te porast cetanskog broja, kao i u mješavini hidro-obrađenog biljnog ulja s dizelskom gorivom. Nije zabilježena značajna promjena destilacijskog reza kod oba tipa mješavina. Dodatak hidrogeniranog biljnog ulja nije značajno utjecao na poboljšanje niskotemperaturnih svojstava, točku zamućenja (eng. cloud point, CP) i točku filtrabilnosti (eng. cold filter plugging point, CFPP) svih ispitanih mješavina. Nešto bolji odziv na dodatak aditiva za poboljšanje točke zamućenja te bolja operabilnost zabilježeni su u mješavini hidroobrađenog biljnog ulja s dizelskim gorivom i FAME. Iz dobivenih rezultata zaključeno je da je dodatak hidroobrađenog biljnog ulja u mješavinu dizelskog goriva i FAME prihvatljivija opcija zbog postizanja višeg cetanskog broja i bolje operabilnosti. Izmjereni rezultati dviju analiziranih mješavina uspoređeni su s rezultatima dobivenim pomoću komercijalnog softvera koji se koristi za procjenu svojstava motornih goriva. Dobiveno je razmjerno dobro slaganje za glavna procijenjena svojstva, osim za cetanski broj. Stoga je zaključeno da se korišteni softverski program može uspješno koristiti za predviđanje svojstava mješavina hidroobrađenog biljnog ulja s dizelskim gorivom te dizelskim gorivom i FAME, osim cetanskog broja. Također, može poslužiti za dobivanje brzih rezultata, mogućnost odabira ciljanih receptura za namješavanje te analizu u laboratoriju. Namješavanje hidroobrađenog biljnog ulja u dizelsko gorivo nastavit će se radi ispitivanja optimiranja receptura te utjecaja na niskotemperaturna svojstva., INA as a motor fuels distributor has an obligation to put on the Croatian market a mandatory share of biofuels in the transport energy mix according to the Act on Market of Biofuels for Road Transport. INA started to use fatty acid methyl esters (FAME) as biocomponent for diesel fuel blending in 2011. The significant increase of biofuels energy share, in next few years requires the introduction of a new type of biocomponents that are suitable for processing in INA refineries. Hydrotreated vegetable oil (HVO) is one type of renewable synthetic fuels, the so called drop-in fuel. HVO is used as a high quality diesel blending component, or as standard diesel fuel, very similar to the gas to liquid (GTL) and biomass to liquid (BTL) fuels. The use of HVO enables better vehicle performance and emission reduction compared with conventional diesel. It is practically aromatics and sulphur-free and has high cetane number. Therefore, HVO shows superior quality compared with convention diesel and FAME. An additional interesting property is its very low density compared to common diesel fuel because INA is occasionally processing the naphthenic West African grades with gas oils of a very high density. The possibility of blending of the HVO component with diesel fuel and iwith the mixture of diesel fuel and FAME was tested in order to meet HRN EN 590 standard for diesel fuel and to examine the impact of HVO addition on important diesel's properties. A maximum amount of 18 vol. % of HVO was added in tested diesel fuel in order to meet EN 590 standard regarding density value. Density decrease and a significant cetane number increase were noticed in blends. In the tested blend of HVO and diesel fuel with FAME the same density like in diesel fuel and cetane number increase like in the HVO and diesel fuel blend were noticed. Distillation range did not change significantly in both types of blends. The added HVO has not significantly influenced the improvement of low temperature properties (cloud point (CP), cold filter plugging point (CFPP)) of all tested blends. The slightly better response of cold flow improver (CFI) additive and achieved better operability was noticed in blend with HVO, diesel fuel and FAME. Considering the results obtained in INA, blending of HVO with diesel fuel and FAME is more acceptable because of achieving better operability and high cetane number. The results obtained for two blends analyzed in laboratory are compared with results calculated by commercial software which is used for estimation of motor fuel properties. A relatively good agreement was achieved regarding the main estimated properties expect the cetane number. It can be concluded that software could be successfully used for predicting the behavior of blend of HVO with diesel fuel or with diesel fuel and FAME mixture, apart from cetane number. It can be used for obtaining fast results, selection of targeted blending recipe and the laboratory analysis. The testing of HVO blending with diesel will be continued in order to optimize the recipe and to examine the influence on low temperature properties.

N-Acryl-N,N′-dicyclohexylurea (A-DCU) homopolymers and copolymers with styrene (St) are prepared under the standard free-radical-initiated polymerization. Copolymers of A-DCU with St prepared under different monomer-to-monomer ratios in the feed, have random composition with an azeotropic point at a ratio of 0.73 (A-DCU) to 0.27 (St). N-Methacryl-N,N′-dicyclohexylurea (MA-DCU) does not homopolymerize, but copolymerizes with St to randomly composed copolymers. Reactivity ratios determined by the Kelen-Tudos method are: r1 (A-DCU) = 0.80; r2 (St) = 0.50, and r1 (MADCU) = 0.18; r2 (St) = 4.84. All copolymers decompose under TGA conditions by a two step mechanism. In the first step, at a temperature of about 200°C separates cyclohexylisocyanate (C6 H11 NCO) under the formation of thermally stable poly(C6 H11 -acrylamido-co-St) and poly(C6 H11-methacrylamido-co-St) which decompose at a temperature of 450°C without the residue.

The title copolymers have been prepared by the free-radical-initiated copolymerization of 2-chlorostyrene (2-ClSt), 4-chlorostyrene (4-ClSt) and 2, 6-dichlorostyrene (2, 6-DClSt) with maleic anhydride (MAn) in toluene at 650C. Copolymers of chlorinated styrenes with MAn prepared under different monomer-to-monomer ratios in the feed have alternating composition. In all cases the mixture of comonomers forms charge-transfer complex monomers (CTC). Initial rate of copolymerization increases with the increase of electron donors in the comonomer feed, and the highest rates were at the equimolar ratios of comonomers in the feed. The thermal stability of the polymers was measured by thermogravimetric analysis in nitrogen. Homopolymers decompose by one-step mechanism while copolymers are more thermostable and decompose by two-step mechanism. Tg’s of homopolymers are lower than Tg’s of copolymers. The number and weight average molecular weights of chlorinated copolymers are higher than those of the corresponding homopolymers.

The free-radical-initiated copolymerization of 2,6-dichloro-styrene (2,6-DClSt), with maleimide (MI), N-methylmaleimide (NMeMI) and N-phenylmaleimide (NPhMI) was carried out in butanone or in toluene at 65°C with different monomer-to-monomer ratios in the feed. The copolymer composition was evaluated by chlorine content in polymers. The reactivity ratios determined by Kelen-Tudos method indicate the random arrangement of monomers in copolymer chains. In all studied systems, azeotropic points were observed at ratios of: 0.5 (2,6-DClSt) to 0.5 (MI) and 0.4 (2,6-DClSt) to 0.6 (NMeMI and NPhMI). Molecular weights of copolymer, which contain equimolar ratio of 2,6-DClSt-co-MI, NMeMI, and NPhMI are: Mw· 10−3 = 46.1; 90.4; 81.4. Mn 10−3 = 27.1; 46.0; 37.0. The copolymers are thermostable, film forming materials, which decompose by one-step mechanism between 400°C, and 500°C. The Tg's are linearly distributed between Tg's of homopolymers and in all cases, single well defined Tg's are obtained.

N(p-Phenoxy-phenyl)methacrylamide (PhOPhMAA) prepared by condensation of methacrylic acid anhydride with p-phenoxy-phe-nylamine readily homopolymerizes and copolymerizes with styrene (St) in the presence of azobisisobutyronitrile as initiator. The copolymers prepared under different monomer-to-monomer ratios in the feed have random composition with an azeotropic point at ratio f 0.65 (St) to 0.35 (PhOPhMAA). Reactivity ratios determined by Kelen-Tudos method are r 1 (St) = 0.61; r 2 (PhOPhMAA) = 0.55. Activation energy determined by Arrhenius method is 71.2 kJ mol -1 . Poly-PhOPhMAA and poly(PhOPhMAA-co-St) are thermally stable up to 350°C under TGA conditions. Tgs and higher transition temperatures are within the thermally stable region.

Synthesis and free-radical-initiated homopolymerization of phenoxy-phenylmaleimide (PhOPhMI) and copolymerization with styrene (St), (α-methylstyrene (αMeSt) and β–methylstyrene (β-MeSt) are described. It was found that alternating copolymers are formed under different monomer-to-monomer ratios in the feed and that the mechanism based on the participation of CT-complex best explains the formation of alternating copolymers. Equilibrium constants of CT-complexes are: K PhOPhMI/St = 0.20 Lmol−1; KPhOPhMI/αMeSt = 0.05 Lmol−1; KPhOPhMI/βMeSt = 0.02 Lmol−1. Homopolymer and co-polymers are film-forming materials, stable up to 350°C under TGA conditions. Tg s and higher transition temperatures are within the thermally stable region.

This paper describes synthesis and evaluation of polymeric additives for improving the flow properties of gas condensate. The additives were prepared by the free-radical initiated polymerization of methacryl esters with styrene and acrylic or methacrylic acid. Polymerization was performed by initiator azo-bis isobutyronitrile in toluene or xylene at 80 °C. The influence of additives structure, composition and molar weight, as well as gas condensate properties on its flow properties was studied. Gas condensate samples from the fields of Kalinovac, Stari Gradac and Molve located in the northern Croatia were used for evaluation of the prepared additives. It was found that the additives efficiency was considerably influenced by their properties and by condensate n-paraffin content and distribution.

U radu je opisana sinteza i polimerizacija akrilnih monomera koji imaju dicikloheksilureu (DCU) u bočnom lancu. Polimerizacijom akril-DCU s etilen-glikol dimetakrilatom (EDMA) do visoke konverzije, u butanonu s benzoil-peroksidom (Bz2O2), pri temperaturi od 70 °C sintetizirani su umreženi kopolimeri različitog sastava. Pri uvjetima kontrolirane termičke razgradnje u TG analizatoru, u temperaturnom području od 100 °C do 500 °C u struji dušika, kopolimeri se razgrađuju dvostupnjevitim mehanizmom. U prvom stupnju, od 180 °C do 250 °C, izdvaja se cikloheksilizocijanat. Ostatci nakon uklanjanja izocijanata termički su stabilni molekulski tiskani (nanoporozni) kopolimeri akril-cikloheksilamida (A-CHA) s EDMA, koji se razgrađuju u jednom stupnju pri temperaturi od 300 °C do 450 °C. Radi usporedbe svojstava molekulski tiskanih, nanoporoznih kopolimera poli(A-CHA-ko-EDMA) s odgovarajućim neporoznim kopolimerima, sintetizirani su neporozni kopolimeri A-CHA s EDMA pri navedenim uvjetima., This paper describes the synthesis and polymerization of acrylic monomers which contain dicyclohexylurea (DCU) as a pendant group. Crosslinked copolymers of these monomers with ethylene glycol dimethacrylate (EDMA) were prepared under the standard free radical initiated polymerization with dibenzoyl-peroxide (Bz2O2) as initiator, in butanone at 70 °C, up to high conversion. It was found that copolymers, regardless of the ratio of comonomers in the feed, thermally decompose by the two-step mechanism under the separation of almost quantitative yield of cyclohexylisocyanate, in the temperature range from 180 °C to 250 °C. The residues left by the removal of isocyanate were thermally stable crosslinked molecularly imprinted copolymers of acryl-cyclohexylamide (A-CHA) with EDMA, which decompose by a one-step mechanism between 300 °C and 450 °C. In order to compare the properties of nanoporous crosslinked copolymers of A-CHA with EDMA with those of nonporous poly(A-CHA-co-EDMA) of the same molar composition, nonporous copolymers were prepared by the polymerization of A-CHA with EDMA under the conditions described above.

U radu je opisana sinteza monomera N-metakril-N,N'-dicikloheksiluree (MA-DCU) i N-metakril-N,N'-diizopropiluree (MA-DiPrU) te polimerizacija s etilen-glikol dimetakrilatom (EDMA). Polimerizacija je provedena u butanonu s benzoil-peroksidom (Bz2O2) do visoke konverzije. Dobiveni su umreženi kopolimeri netopljivi u organskim otapalima. Neovisno o sastavu, kopolimeri se razgrađuju dvostupnjevitim mehanizmom pri temperaturama od 180 °C do 450 °C uz izdvajanje cikloheksilizocijanata (C6H11NCO), odnosno izopropilizocijanata (C3H7NCO) pri temperaturi od 180 °C do 250 °C. Ostatak nakon izdvajanja izocijanata je termički stabilan nanoporozni umreženi kopolimer metakril-cikloheksilamida (MA-CHA), odnosno metakril-izopropilamida (MA-iPrA) s EDMA. Ti se kopolimeri razgrađuju u jednom stupnju pri temperaturama od 280 °C do 450 °C. Sintetizirani su i neporozni kopolimeri MA-CHA, odnosno MA-iPrA s EDMA (modelni kopolimeri) radi usporedbe svojstava s odgovarajućim nanoporoznim kopolimerima., The present paper describes the synthesis of monomers N-methacryl-N,N’-dicyclohexylurea (MA-DCU) and N-methacryl-N,N’-diisopropylurea (MA-DiPrU) and their polymerization with ethylene glycol dimethacrylate (EDMA). Polymerization were carried out in butanone by using dibenzoyl-peroxide (Bz2O2) up to high conversion. All prepared copolymers are insoluble in common organic solvent. Crosslinked copolymers decompose thermally at temperatures from 180 °C to 450 °C under the separation of cyclohexylisocyanate (C6H11NCO) or isopropylisocyanate (C3H7NCO) at temperature between 180 °C and 250 °C. Residues after the removal of isocyanate are thermally stable nanoporous crosslinked copolymers of methacryl-cyclohexylamide (MA-CHA) or methacryl-isopropylamide (MA-iPrA) with EDMA, which decompose by a one-step mechanism between 280 °C and 450 °C. Nonporous model copolymers of MA-CHA and MA-iPrA with EDMA were also prepared in order to compare their properties with the properties of corresponding nanoporous copolymers.

The title compounds have been prepared by the addition of acrylic acid and methacrylic acid to dicyclohexylcarbodiimide (DCC). N-Acryl-N,N′-dicyclohexylurea (Acryl-DCU) homo-polymerizes and copolymerizes with α-methylstyrene (αMeSt), while Methacryl-DCU does not polymerize under the standard free-radical-initiated polymerization. Copolymers of Acryl-DCU with αMeSt prepared under different monomer-to-monomer ratios in the feed have random composition with an azeotropic point at ratio of 0.75 (Acryl-DCU) to 0.25 (αMeSt). Reactivity ratios determined by the Kelen-Tudos method are r1 (Acryl-DCU) = 0.72 and r2 (αMeSt) = 0.07. Poly(Acryl-DCU) and copolymers with αMeSt decompose under the TGA conditions by a two step mechanism. In the first step between 180 and 250°C, cyclohexylisocyanate separates by degradation of dicyclohexylurea in the side chain, while the thermally stable residue represents the poly(cyclohexylacrylamide) and copolymers with αMeSt.

Faraday tomography of polarimetric observations at low frequency is a unique tool to study the structure of the magneto-ionic interstellar medium (ISM) based on Faraday depth. LOFAR data below 200 MHz revealed a plethora of features in polarization, whose origin remains unknown. Previous studies highlighted the remarkable association of such features to tracers of the magnetized-neutral ISM, as interstellar dust and atomic hydrogen (HI). However, the physical conditions responsible for the correlation between magneto-ionic and neutral media are yet to be clarified. In this letter we investigate further the correlation between LOFAR data and HI observations at 21cm from the Effelsberg-Bonn HI Survey (EBHIS). We focus on the multiphase properties of the HI gas. We present the first statistical study on the morphological correlation between LOFAR tomographic data and the cold (CNM), luke-warm (LNM), and warm (WNM) HI phases, separately. We use the Regularized Optimization for Hyper-Spectral Analysis (ROHSA) approach to decompose the HI phases based on the Gaussian decomposition of the HI spectra. In at least two fields of view -- Fields 3C196 and A -- out of four -- Fields B and C -- we find a significant correlation between LOFAR and EBHIS data using the Histograms of Oriented Gradients (HOG). The absence of correlation in Fields B and C is caused by low signal-to-noise ratio in polarization. The observed HOG correlation in Fields 3C196 and A is associated with all HI phases and it is surprisingly dominant in the CNM and LNM phases. We discuss possible mechanisms that would explain the correlation between CNM, LNM, and WNM, with polarized emission at Faraday depths up to 10 rad m$^{-2}$. Our results show how the complex structure of the ionic medium seen by LOFAR data is tightly related to phase transition in the diffuse and magnetized neutral ISM traced by HI spectroscopic data., 9 pages, 10 figures, accepted for publication in A&A