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The effects of different contents of two metallocene propylene-based m-EPR elastomers on structure, morphology, thermal and dynamic mechanical properties of the isotactic polypropylene/m-EPR blends were investigated. The both m-EPR copolymers have been built in iPP matrix as amorphous phase. However, the nucleation effect at lowest addition (2.5 vol%) and the solidification effect along with increased m-EPR's additions have caused changes of the crystallinity degree and the size of spherulites in the iPP matrix. Higher degree of miscibility/compatibility of the iPP/m-EPR2, with lower viscosity has been observed. Homogeneous dispersion of m-EPR particles as well as their radial distribution has been observed.

The effects of two metallocene ethylene-propylene-based elastomers (m-EPR1 and m-EPR2) differing in molecular mass and viscosity on mechanical, rheological and interfacial properties were compared. The m-EPR elastomers were added to iPP in 2.5, 5, 10, 15, and 20 vol.%. Torque values, elongation at break and impact strength measured of the iPP/m-EPR1 blends were higher than the iPP/m-EPR2 blends due to higher molten viscosity of m-EPR1 than m-EPR2 copolymer. Slight differences in Young moduli as well as in tensile strength at yield and at break might indicate that tensile properties of iPP/m-EPR blends were not significantly affected by difference in viscosity or molecular mass, miscibility and spherulite size. Optimization diagrams indicated the metallocene m-EPR copolymers are efficient impact modifiers for polypropylene and showed good balancing of mechanical properties in iPP/m-EPR blends. V delu smo preučevali vpliv dveh metalocenskih elastomerov na osnovi etilena/propilena (m-EPR1 in m-EPR2), ki sta se razlikovala v molekulski masi in viskoznosti, na mehanske, reološke in medpovršinske lastnosti. V iPP matrico smo dodali 2.5, 5, 10, 15 in 20 vol.% m-EPR elastomera. Ugotovili smo, da imajo mešanice iPP/m-EPR1 višje vrednosti torzijskega momenta mešanja, raztezka ob pretrgu in udarne žilavosti kot mešanice iPP/m-EPR2 zaradi višje viskoznosti taline m-EPR1 kot m-EPR2 elastomera. Manjše razlike v Youngovem modulu, meji plastičnosti in natezni trdnosti pri pretrgu kažejo, da natezne lastnosti mešanic iPP/m-EPR niso v veliki meri odvisne od viskoznosti ali molekulske mase, mešljivosti in velikosti sferolitov. Optimizirani diagrami kažejo, da so m-EPR elastomeri učinkoviti modifikatorji žilavosti za polipropilen in kažejo ugodno ravnotežje mehanskih lastnosti mešanic iPP/m-EPR.

The effects of different silica (SiO2) types and different contents of two metallocene propylene-based m-EPR elastomers (differing in molecular weight and viscosity) on interfacial properties, structure and morphology of isotactic polypropylene/SiO2/m-EPR composites were investigated. Four silica fillers differing in size (nano- vs. micro-) and surface properties (hydrophilic vs. hydrophobic i.e. polar vs. non-polar) were chosen and added in 4 vol% to isotactic polypropylene. The m-EPR elastomers were added to iPP/SiO2 96/4 composites as possible impact modifier and compatibilizer at the same time in 5, 10, 15, and 20 vol% per 100 vol% of composites (phr). The investigation confirmed the overall prevailing of separated morphology of ternary iPP/SiO2/m-EPR composites, i.e. selectivity of dispersed m-EPR and silica particles toward iPP matrix as was predicted on the basis of adhesion properties. The increase of crystallinity degree and spherulite size with addition of m-EPR elastomers indicated significant solidification effect of added elastomers in addition to opposite nucleation effect of silica particles owing to surface character of filler. The effects of different silica fillers and different contents of two m-EPR elastomers were discussed within the context of morphology/structure-adhesion property relationships of the iPP/SiO2/m-EPR composites.

Rheological and mechanical properties (tensile and impact properties) as well as the mechanical profiles of ternary isotactic polypropylene/silica/elastomer (iPP/SiO2/m-EPR metallocene catalyzed ethylene-propylene rubber) composites were investigated and discussed. The effects of two metallocene ethylene-propylene-based elastomers (m-EPR) differing in molecular weight/viscosity and their content on iPP/silica composites with different silica types differing in size (nano- vs. micro-) and surface properties (untreated vs. treated) were investigated. The two m-EPR elastomers were added to iPP/SiO2 96/4 composites as possible impact modifier and compatibilizer at the same time in 5, 10, 15, and 20 vol% per hundred volume parts of composites. The effects of different silica fillers and two m-EPR rubbers were discussed within the context of structure-morphology-mechanical property relationships of these iPP/SiO2/m-EPR composites. Tensile and impact strength properties were mainly influenced by combined competetive effects of stiff filler and tough m-EPR elastomer so sinergistic effect was also observed. The ductility of these composites was affected additionally by spherulite size of the iPP matrix due to the difference in nucleation abilities of silica fillers enabled by prevailing separated morphology observed in iPP/SiO2/m-EPR composites.

Evidence is presented that all three theoretically predicted modes of phase separation take place in the ternary system polysulfone(PSf)/ N , N -dimethyl acetamide(DMA)/water during the process of wet phase separation (WPS). The elementary process of solidification is reconsidered with regard to the (non-) equilibrium phase separation. Cast solutions with more than 15 wt% of PSf undergo nucleation and growth of the polymer lean phase with formation of separation membranes characterised by a cellular structure. When cast solutions with about 5–7 wt% of PSf undergo WPS, somewhere inside the ternary system conditions are established so that alongside other solidified PSf structures the bicontinuous spinodal structures superimposed by bead-like structures are also formed. Variety of lacy PSf structures with less/more polymer beads is the manifestation of the primary phase separation by the spinodal mode superimposed by the secondary phase separation taking place by heterogeneous nucleation and growth of the polymer rich phase mode. Latex formation during the WPS will also be explained. Skin formation on the cast solution – coagulation bath interface by direct accumulation of polymer is established regardless of the PSf content in the cast solution.

Mechanical properties of isotactic polypropylene/wollastonite/styrene rubber block copolymers (iPP/wollastonite/SRBC) composites were studied as a function of elastomeric poly(styrene-b-ethylene-co-butylene-b-styrene) triblock copolymer (SEBS) and SEBS grafted with maleic anhydride (SEBS-g-MA) content from 0 to 20 vol%. Microphase morphology was stronger influenced by SRBC elastomers than by different wollastonite types. Higher encapsulation ability of SEBS-g-MA than SEBS caused more expressive core-shell morphology and consequently higher notched impact strength as well as yield parameters, but lower Young's modulus. Higher ductility of the composites with SEBS than with SEBS-g-MA has been primarily caused by better miscibility of the polypropylene chains with SEBS molecules. Surface properties of components and adhesion parameters also indicated that adhesion at SEBS-g-MA/wollastonite interface, which was stronger than the one at the SEBS/wollastonite interface, influenced higher encapsulation of wollastonite particles by SEBS-g-MA. POLYM. ENG. SCI., 47:1873–1880, 2007. © 2007 Society of Plastics Engineers

Polypropylene/talc/SEBS (SEBS-g-MA) composites. Part 2. Mechanical properties Isotactic polypropylene/styrenic rubber block copolymer blends (iPP/SRBC) as well as the iPP/talc/SRBC composites with 12 vol % of aminosilane surface treated talc were studied by the measurement of mechanical properties (tensile properties and notched impact strength). Mechanical properties and their relation with the structure of polypropylene blends and composites were investigated as a function of poly(styrene-b-ethylene-co-butylene-b-styrene) triblock copolymer (SEBS) and the SEBS grafted with maleic anhydride (SEBS-g-MA) content in the range from 0 to 20 vol % as elastomeric components. Elongation at yield of the iPP/talc/SEBS-g-MA composites and impact strength of the iPP/talc/SEBS composites show synergistic effect at high elastomer content (20 vol %). Higher molecular weight (and consequently higher viscosity, elasticity and impact strength) of thicker SEBS layers around highly oriented talc crystals and higher miscibility or interactivity of SEBS than SEBS-g-MA with iPP chains seem to contribute to enormous impact strength of the iPP/talc/SEBS composites. On the other side, a higher extent of encapsulation and disorientation of talc crystals by the SEBS-g-MA than by SEBS copolymer, and lower molecular weight of the SEBS-g-MA than SEBS copolymer may contribute to higher elongation at yield of the iPP/talc/SEBS-g-MA composite.

Asymmetric and porous polysulfone (PSf) membranes were prepared by wet phase separation. Binary (PSf)/N,N-dimethylacetamide (DMA) solutions with polymer concentrations of 12.5–30 wt % were cast in thicknesses of 80–700 μm and immersed in a coagulation bath of pure water. The morphology of the formed membranes' cross sections consisted of a cellular structure and macrovoids; the cellular structure density was highest when the cast solution contained about 21 wt % PSf, regardless of the cast thickness. The membranes' pure water permeability decreased as the cast thickness increased. The instantaneous onset of the turbidity, regardless of the PSf content and cast thickness, its steep growth, and relatively high end value were the main characteristics of the turbidity phenomena taking place during the formation of the protomembranes. Again, the membrane-forming system with a PSf/DMA solution with about 21 wt % polymer, regardless of the cast thickness, had the highest turbidity end value. The shrinkage of the cast solutions into the corresponding protomembrane was also examined quantitatively. Inverse experiments showed that the direction of the gravitation field had no influence on the shrinkage of the membrane-forming ternary system or the membranes' morphology and its water permeability. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1667–1674, 2005

Among thermoplastics, polypropylene is outstanding with respect to its attractive combination of low cost, low weight, heat distortion temperature above 100°C, and extraordinary versatility in terms of properties and applications. With the appropriate modification, it is possible to improve the existing properties of the polypropylene, or even obtain the new ones. As a result of its originally superior properties, polypropylene is commonly used in medical purposes, where it has to undergo the process of sterilization beforehand. The sterilization of the polypropylene in medicine is most often being carried out with low dose of gamma irradiation, which can influence the changes of properties of both the polymeric matrix and modifiers. Therefore, the purpose of our research work was to determine the mechanical properties of unirradiated and gamma irradiated isotactic polypropylene (iPP) composites with talc filler and poly-(styrene-b-ethylene-co-butylene-b-styrene) block copolymer, grafted with maleic anhydride (SEBS-g-MA) as elastomeric modifier, as well as of corresponding binary blends. Unirradiated and gamma irradiated composites and blends were characterized by tensile measurements, measurements of notched impact strength and FTIR spectroscopy. The effects of composition and gamma irradiation on the properties of the iPP composites and blends are discussed, with emphasis on the study of the stabilizing effect of talc in irradiated iPP composites.

The structure-property relationships of isotactic polypropylene (iPP)/styrenic block copolymer blends filled with talc were examined by optical and scanning electron microscopy, wide-angle X-ray diffraction, and tensile- and impact strength measurements. The composites were analyzed as a function of the poly(styrene-b-ethylene-co-propylene) diblock copolymer (SEP) and the poly(styrene-b-butadiene-b-styrene) triblock copolymer (SBS) content in the range from 0 to 20 vol % as elastomeric components and with 12 vol % of aminosilane surface-treated talc as a filler. Talc crystals incorporated in the iPP matrix accommodated mostly plane-parallel to the surface of the samples and strongly affected the crystallization process of the iPP matrix. The SBS block copolymer disoriented plane-parallel talc crystals more significantly than the SEP block copolymer. The mechanical properties depended on the final phase morphology of the investigated iPP blends and composites and supermolecular structure of the iPP matrix because of the interactivity between their components.

Although isotactic polypropylene (iPP) has become one of the largest and fastest growing polymeric materials, some disadvantages in its properties, like poor stability to gamma (g) irradiation, may impede its growth in commercial use. The popularity of g irradiation use to sterilize iPP and iPP composites devices is increasing. The purpose of our research work was to examine the effects of talc and low dose g irradiation on mechanical properties and the morphology of iPP and iPP/talc composites. The samples were prepared in a Brabender kneading chamber and by compression molding on a laboratory press. The iPP and iPP/talc composites were characterized by tensile testing, measurements of notched impact strength, FTIR spectroscopy, differential scanning calorimetry, optical microscopy, scanning electron microscopy and wide angle X-ray diffraction. The role of untreated talc or talc surface treated with aminosilanes as well as the influence of g irradiation on mechanical properties and the morphology of modified iPP is discussed.

The effects of different silica loadings and elastomeric content on interfacial properties, morphology and mechanical prop- erties of polypropylene/silica 96/4 composites modified with 5, 10, 15, and 20 vol % of poly(styrene-b-ethylene-co-butylene-b-styrene) SEBS added to total composite volume were investigated. Four silica fillers differing in size (nano- vs. micro-) and in surface proper- ties (untreated vs. treated) were chosen as fillers. Elastomer SEBS was added as impact modifier and compatibilizer at the same time. The morphology of ternary polymer composites revealed by light and scanning electron microscopies was compared with morphology predicted models based on interfacial properties. The results indicated that general morphology of composite systems was determined primarily by interfacial properties, whereas the spherulitic morphology of polypropylene matrix was a result of two competitive effects: nucleation effect of filler and solidification effect of elastomer. Tensile and impact strength properties were mainly influenced by combined competetive effects of stiff filler and tough SEBS elastomer. Spherulitic morphology of polypropylene matrix might affect some mechanical properties additionally. V C 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41486.

Various silica grades differing in particle size (micro- versus nanosilica) and surface modification (untreated versus modified surface) have affected interfacial and mechanical properties of compression-molded polypropylene composites with 2, 4, 6, 8 vol% of added silica. Mechanical properties have been influenced primarily by combination of stiff fillers and tough polypropylene matrix and additionally by restructured matrix. Namely, silica particles with different surface properties have influenced nucleation and spherulite growth differently affecting thus tensile properties of the composites. All composites exhibited best tensile strength in silica content range 2–6 vol%.

The direct accumulation of polymer, the nucleation and growth of the polymer lean as well as the polymer rich phase and the spinodal phase separation are postulated as four elementary processes of the mechanisms of the polymeric membrane formation by wet-phase separation. With the study of five different polymer/solvent:water systems they are discriminated by the investigation of the turbidity and the shrinkage phenomena taking place during (proto)membrane formation, as well as by the measurement of the pure water permeability and by the inspection of the membranes’ cross-section morphology. The general scheme of membrane formation mechanisms is arranged by gathering the groups of different modes of mass transport and the group of nonsolvent/solvent/polymer forms of solidification as elementary processes; by forming combinations of the so postulated elementary processes in time and space particular mechanisms are established.

The compatibilizing effect of the triblock copolymer poly(styrene-b-butadiene-b-styrene) (SBS) on the morphology and mechanical properties of immiscible polypropylene/polystyrene (PP/PS) blends were studied. Blends with three different weight ratios of PP and PS were prepared and three different concentrations of SBS were used for investigations of its compatibilizing effects. Scanning electron microscopy (SEM) showed that SBS reduced the diameter of the PS-dispersed particles as well as improved the adhesion between the matrix and the dispersed phase. Transmission electron microscopy (TEM) revealed that in the PP matrix dispersed particles were complex “honeycomblike” aggregates of PS particles enveloped and joined together with the SBS compatibilizer. Wide-angle X-ray diffraction (WAXD) analysis showed that the degree of crystallinity of PP/PS/SBS slightly exceeded the values given by the addition rule. At the same time, addition of SBS to pure PP and to PP/PS blends changed the orientation parameters A110 and C significantly, indicating an obvious SBS influence on the crystallization process in the PP matrix. SBS interactions with PP and PS influenced the mechanical properties of the compatibilized PP/PS/SBS blends. Addition of SBS decreased the yield stress and the Young's modulus and improved the elongation at yield as well as the notched impact strength in comparison to the binary PP/PS blends. Some theoretical models for the determination of the Young's modulus of binary PP/PS blends were used for comparison with the experimental results. The experimental line was closest to the series model line. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 69: 2625–2639, 1998

Compatibilizing effects of diblock copolymer polystyrene-block-poly(ethylene-co-propylene) (SEP) on the morphology and mechanical properties of immiscible blends of poly(propylene) (PP) and polystyrene (PS) were investigated. Notched impact strength, yield stress, elongation at yield and Young's modulus were determined as a function of different weight ratios of PP and PS and different amounts of added SEP as well. Scanning electron microscopy revealed a two-phase morphology of PP/PS blends, which exhibit poor mechanical properties. Even 2,5 wt.-% of SEP added to PP/PS blends can improve the notched impact strength and elongation at yield compared to non-compatibilized PP/PS blends. 10 wt.-% of SEP compatibilizer converted the brittle PP/PS blend to quite impact-resistant polymeric material. Mechanical properties were improved because of the morphological changes and increased interfacial adhesion as a result of SEP localization between PP and PS phases. An analysis of yield stress data in terms of theoretical models showed that yield stress values of binary PP/PS blends can be predicted with Nielsen's model.

The aim of this study was to compare the effects of different silica grades on the structure and morphology of isotactic polypropylene (iPP)/silica composites to better understand their structure-property relationships. Isotactic polypropylene composites with 2, 4, 6, 8 vol % of added silica fillers differing in particle size (micro- vs. nanosilica) and surface modification (untreated vs. treated surface) were prepared by nonisothermal compression molding and characterized by different methods. The addition of all silica fillers grades to the iPP matrix significantly influenced the spherulitic morphology, while phase characteristics of the iPP matrix seemed to be unaffected. Surface modification of silica fillers exhibited stronger effects on spherulite size than size of silica particles. Nonpolar silica particles, more miscible or compatible with iPP chains than polar silica particles, enabled better spherulitic growth. The spherulite sizes tended to reach equal values at 8 vol % of added silicas showing that spherulite size became independent of filler concentration and surface modification above optimum filler concentration. V C 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 000: 000-000, 2012

We report on novel observations on the appearance of macrovoids in the ternary cellulose acetate (CA)/acetone (ACE)/water membrane forming system. The membranes are prepared by the wet phase separation whereby the cast solution is composed of ACE and polymer, and the coagulation bath is pure water only. It is found that the macrovoid formation in a 12.5 wt.% cast solution strongly depends on the cast solution thickness: macrovoids appear at the thickness of 500 μm but not at 150 and 300 μm.

Mechanical properties and adhesion phenomena of isotactic polypropylene/wollastonite/metallocene propylene-ethylene copolymers (iPP/W/EPR) composites were studied as a function of metallocene propylene-based copolymers content from 0 to 20 vol%. The composites with different surface treated wollastonites and two types of EPR have shown similar behavior of most mechanical properties except elongation at break and impact strength respective of the difference in some characteristics of used EPR elastomers. The increase and the difference in elongation at break could be explained by renewed spherulitic morphology of the iPP matrix. Stronger interactions between EPR-1 and two used types of wollastonites than between EPR-2 and corresponding wollastonites concluded from the surface properties led to the difference in impact strength behavior. The determined mechanical properties confirm the assumption coming out of structural investigations that metallocene EPR elastomers are rather efficient impact modifiers than encapsulation compatibilizers for the iPP/wollastonite composites. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers

Supermolecular structure of isotactic polypropylene/ wollastonite/metallocene propylene–ethylene copolymers (iPP/W/EPR) composites was studied as a function of elastomer content (from 0 to 20 vol%) by optical, scanning, and transmission electron microscopy, wide-angle X-ray diffraction, and differential scanning calorimetry. Both, wollastonite and dispersed EPR particles, homogeneously incorporated into the iPP matrix, and affected the final phase structure and morphology of the iPP/wollastonite/EPR composites. Wollastonite particles were orientated plane-parallel to the sample surface and hindered spherulite growth of the iPP matrix. EPRs enhanced plane-parallel orientation of wollastonite and simultaneously enhanced the spherulite and crystallite growth in the iPP matrix during the solidification of polymer melt. Ternary iPP/ wollastonite/EPR composites exhibited significant prevalence of separated microphase morphology (over core-shell morphology) because of constitution similarity of P-E and iPP chains. POLYM. COMPOS., 30:1007– 1015, 2009. a 2008 Society of Plastics Engineers

Determination of the structure-property relationships of isotactic polypropylene blends with different elastomers demands complex investigation of phase structure, morphology, adhesion and mechanical properties. The comparison of phase morphology of isotactic polypropylene modified with styrenic rubber block copolymers (SEBS, SEBS-g-MA) and propylene-based metallocene copolymers (EPR-1, EPR-2) with elastomer content 0-20 vol% was performed by light microscopy, scanning electron microscopy (SEM) and transmision electron microscopy (TEM). Homogenously dispersed elastomer particles differed in size due to the difference in viscosity. The addition of different types of elastomers affected crystallization behaviour of polypropylene matrix and consequently morphology by competitive nucleation and solidification effects. As a result of these effects the difference in spherulite size between blends with different elastomers was revealed by polarization micrographs. It seems that the ethylene-propylene copolymers exibited some degree of miscibility or co-crystallizability with polypropylene in distinct to styrenic rubber block copolymers.

Supermolecular structure of isotactic polypropylene/ wollastonite/styrenic rubber block copolymers composites were studied as a function of elastomeric poly(styrene-b-ethylene-co-butylene-b-styrene) triblock copolymer (SEBS) and the SEBS grafted with maleic anhydride (SEBS-g-MA) content (from 0 to 20 vol%) by optical, scanning, and transmission electron microscopy, wide-angle X-ray diffraction and differential scanning calorimetry. Wollastonite particles disturbed the spherulitization of polypropylene matrix. Both elastomers affected the crystallization of polypropylene matrix mainly by solidification effect. Although SEBS-gMA encapsulated wollastonite particles more expressive than SEBS forming thus core-shell morphology in higher extent, scanning electron micrographs indicated more constrained wollastonite particles in fractured surfaces of composites with SEBS elastomer. Moreover, SEBS-gMA disorientated wollastonite particles and affected reorientation of the polypropylene crystallites stronger than SEBS elastomer. POLYM. ENG. SCI., 47:2145–2154, 2007. a 2007 Society of Plastics Engineers

Isotactic polypropylene/styrenic rubber block copolymer blends (iPP/SRBC) as well as the iPP/talc/SRBC composites with 12 vol% of aminosilane surface treated talc were studied by optical and scanning electron microscopy, and by wide angle X-ray diffraction. Structure of polypropylene blends and composites was investigated as a function of poly(styrene-b-ethylene-co-butylene-b-styrene) triblock copolymer (SEBS) and the SEBS grafted with maleic anhydride (SEBS-g-MA) content in the range from 0 to 20 vol% as elastomeric components. Both copolymers (SEBS and SEBS-g-MA) affected the iPP spherulite size in blends by nucleation and solidification effects during crystallization. Talc crystals, homogeneously incorporated in the iPP matrix, accommodated mostly plane-parallel to the surface of the samples and strongly affected crystallization process of the iPP matrix disturbing well-developed spherulitic morphology of polypropylene. Both, SEBS and SEBS-g-MA block copolymers, encapsulated talc crystals, thus forming core–shell morphology in significantly higher extent than the poly(styrene-b-butadiene-b-styrene) triblock (SBS) and the poly(styrene-b-ethylene-co-propylene) diblock copolymer (SEP) in iPP/talc composites, studied previously. SEBS-g-MA encapsulated and disorientated plane-parallel talc crystals more significantly than the SEBS block copolymer.

Polypropylene blends and composites with 5, 10, and 15 vol % of EPDM and 2, 4, and 6 vol % of untreated and treated wollastonite filler were examined by applying different techniques. Elastomeric ethylene/propylene/diene terpolymer (EPDM) component and wollastonite influenced the crystallization process of isotactic polypropylene (iPP) matrix in different ways. The nucleation of hexagonal β-iPP, the increase of overall degree of crystallinity, and crystallite size of iPP were more strongly affected by wollastonite than the addition of EPDM was. Both ingredients also differently influenced the orientation of α-form crystals in iPP matrix. Wollastonite increased the number of a*-axis-oriented α-iPP lamellae plan parallel to the sample surface, whereas the addition of EPDM reoriented the lamellae. The orientation parameters of ternary composites exhibited intermediate values between those for binary systems because of the effects of both components. EPDM elastomer considerably affected well-developed spherulitization of iPP, increasing the spherulite size. Contrary to EPDM, because of nucleating ability or crystal habit, wollastonite caused significantly smaller iPP spherulites. Small spherulites in ternary iPP/EPDM/wollastonite composites indicated that the wollastonite filler (even in smallest amounts) exclusively determined the morphology of ternary composites. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 4072–4081, 2004