Evaluation of plant-based oils for production of offset printing ink

The oils and solvents are the main components of the printing ink, and the chemical composition of the ink could be harmful or toxic to human health and the environment. Therefore, there is an increasing demand to develop inks containing green, biobased, sustainable, and renewable raw materials instead of petrochemical substances. In this study, flaxseed oil (FO), pomegranate seed oil, plum kernel oil (PKO), and grape seed oil (GSO) were selected to produce offset printing inks. Pinus pinaster (P. pinaster) resin was also used in the formulation of inks to examine the effects of natural resin on ink together with vegetable oils. The phenolic content was analyzed for the resin and oils to figure out their potential antioxidant and bioactive characteristics. Optical and rheological tests were applied to evaluate the printability of the inks. L*a*b*, ΔE, density, and gloss tests were performed for optical evaluation. The viscosity, tack, and rub resistance tests were applied to perform rheological analysis. The biobased, environmental friendly, and self-drying (cold set) offset printing inks were obtained using natural pine resin and three different plant-based oils FO, PKO, and GSO. The printability analysis of the inks figured out the potential usage of plant-based oils in the offset printing ink formulation.     

Offset printing inks based on rapeseed oil and sunflower oil. Part II: Varnish and ink formulation

Two sets of variable oil length, alkyd resins modified by sunflower oil (SOA) and by rapeseed oil (ROA), were evaluated in offset formulations with mineral oils as diluent. The more suitable alkyds for this kind of application were determined. In a second experiment, hydrocarbon solvents were substituted by the fatty acid methyl esters derived from rapeseed oil or sunflower oil to produce ecologically friendly offset printing inks. Finally, the ROA and the SOA were associated with the methyl esters derived from the same vegetable oil. New properties of the varnishes composed of a vegetable diluent were evaluated. The quickset formulations with the methyl esters do not need important modifications, as opposed to the heatset formulations.     

The use of natural (Pinus pinaster) resin in the production of printing ink and the printability effect

Alkyd resins are generally used in the production of printing inks. All industries look for alternative raw materials in the production of ink with the growing inclination toward using natural products. Resins forming the vehicle of the ink to be obtained from natural resources will provide benefits for the environment, nature, and living creatures. The aim of the study was to promote the use of natural resin in the ink system. Natural Pinus pinaster resin was added into vegetable and mineral oil-based solvents in pure form with alkyd resin in different amounts and ink varnishes of different combinations were prepared. Then, printing inks were produced from these varnishes in pure and hybrid form. Following the assessment of the rheological properties of the inks prepared, printing tests were conducted to assess the printing quality parameters. Ideal mixing ratios of the natural resins in the ink were determined for printability. The environmental importance and advantages of the use of natural resins were discussed. Recommendations were given in line with the results to encourage widespread use of natural resins in near future.     

An ecological approach to printing industry: Development of ecofriendly offset printing inks using vegetable oils and pine resin as renewable raw materials and evaluation of printability

Petroleum-based solvents and synthetic resins are used as raw materials for the production of varnish, which is one of the main components of offset printing inks. These petrochemical compounds that are released to the surrounding in printing process demonstrates harmful effects on environment and human health. In the light of these facts, this study was carried out to investigate the use of renewable natural resources for offset printing inks production to lower environmental impacts and protect human health. In this study, different vegetable-based offset printing inks were developed with safflower oil (SO); grape seed oil (GSO) and Pinus pinaster resin (PPR) and printability analysis were performed. To understand the effect of pine resin in the ink formulation an ink sample with mineral oil (MO) was also produced. Printing tests were carried out with coated papers and the IGT C1 offset printability tester. Color, gloss, rub resistance, viscosity and tack values were measured on the test prints. Comparison of results with standard values figured out the suitability of using the newly developed offset printing inks for printing industry. The color difference values of color differences were in range of tolerance value. The density value of SO-PPR ink was found as same with standard values while the density value GSO-PPR and MO-PPR inks were measured close to standards as 1.45, 1.42, and 1.46, respectively. The results of printability analysis demonstrated appropriate utilization of the renewable sources for ecological development of offset printing inks.     

In-line monitoring of the conversion in UV-cured printed layers by NIR spectroscopy in an offset printing press

In this study, it was demonstrated that the conversion in printed layers of UV-cured printing inks and varnishes can be determined in-line in a printing press by NIR reflection spectroscopy supported by chemometric methods. Layers were printed with a thickness of ∼1.2 g m⁻² for a printing ink and ∼2.8 g m⁻² for a printing varnish. Quantitative analysis of the spectral data was carried out with calibration models based on the partial least squares (PLS) algorithm. In-line monitoring tests were performed at a large-scale sheet-fed offset printing press in order to evaluate the predicting performance of the calibration models under process conditions. Different conversions in the layers were induced by variation of the irradiation dose. The predicting errors were 4.5% for the ink and 4.0% for the varnish. The printing speed was found to have no significant influence on the precision of the measurements.     

Synthesis and curing behavior of diimide–diacid-modified saturated polyester

The polyester and diimide–diacid-modified polyester prepolymer have been synthesized with different molecular weights through melt polycondensation of 1, 6-hexanediol (HD), trimethylol propane (TMP), isophthalic acid (IPA), diimide diacid, and phthalic anhydride (PA) at various molar ratios. The prepolymers were then mixed with an equivalent phenol-blocked TDI and /or HMDI in m-cresol in deriving the polyester urethane varnishes. The degree of crosslinkage and thermal behavior have been investigated here. © 1993 John Wiley & Sons, Inc.     

Complexation of Zirconium Alkoxides with 3-Pentenoic Acid and Hydrolytic Stability of Their Products

Reactions of Zr(OPr ⁿ )₄ and Zr(OBu ⁿ )₄ with 3-pentenoic acid (PA) in 1:1 molar ratio were studied in propanol and butanol solution at room temperature by the sol–gel process. The complexations were investigated by ¹³C{¹H}, ¹H-NMR and FTIR spectroscopy. The ¹³C{¹H}, ¹H-NMR and FTIR spectra showed that PA completely reacted with Zr(OPr ⁿ )₄ and Zr(OBu ⁿ )₄. The new products were hydrolyzed by water in a ratio of 1:4 (Zr(OR ⁿ )₄/ H₂O, R = propyl, butyl). The stability of hydrolyzed products was investigated spectroscopically. After hydrolysis, it was observed that no PA was released from the complexes, [Zr(OPr ⁿ )₃(PA)] and [Zr(OBu ⁿ )₃(PA)], under the reaction conditions.     

Fatty acid transport across lipid bilayer planar membranes

The transport of palmitic acid (PA) across planar lipid bilayer membranes was measured using a high specific activity [¹⁴C]palmitate as tracer for PA. An all-glass trans chamber was employed in order to minimize adsorbance of PA onto the surface. Electrically neutral (diphytanoyl phosphatidylcholine) and charged (Azolectin) planar bilayers were maintained at open electric circuit. We found a permeability to PA of (8.8±1.9)×10⁻⁶ cm s⁻¹ (n=15) in neutral and of (10.3±2.2)×10⁻⁶ cm s⁻¹ (n=5) in charged bilayers. These values fall within the order of magnitude of those calculated from desorption constants of PA in different vesicular systems. Differences between data obtained from planar and vesicular systems are discussed in terms of the role of solvent, radius of curvature, and pH changes.     

Development of karanja oil based offset printing ink in comparison with linseed oil

The conventional offset lithographic printing ink is mainly based on linseed oil. But in recent years, due to stiff competition from synthetic substitutes mainly from petroleum products, the crop production shrinks down to an unsustainable level, which increases the price of linseed oil. Though soyabean oil has replaced a major portion of linseed oil, it is also necessary to develop alternate cost effective vegetable oils for printing ink industry. The present study aims to evaluate the performance of karanja oil (Pongamia glabra) as an alternative of linseed oil in the formulation of offset printing ink because karanja oil is easily available in rural India. Physical properties of raw karanja oil are measured and compared with that of alkali refined linseed oil. Rosin modified phenolic resin based varnishes were made with linseed oil as well as with karanja oil and their properties are compared. Sheetfed offset inks of process colour yellow and cyan is chosen to evaluate the effect of karanja oil in ink properties. In conclusion, karanja oil can be accepted as an alternate vegetable oil source with its noticeable effect on print and post print properties with slower drying time on paper. However, the colour and odour of the oil will restrict its usage on offset inks.     

Nonisothermal crystallization and morphology of crystallites of polyamide 66 and copolyamide 66 containing 2‐carboxyethyl phenyl phosphinic acid

Flame‐retardant polyamide 66 with a 10% mass fraction of 2‐carboxyethyl phenyl phosphinic acid (CEPPA) hexamethylene diamine salt (PA66‐10) was fabricated in our previous study. In this study, the nonisothermal crystallization kinetics of pure polyamide 66 (PA66‐0) and PA66‐10 were measured by differential scanning calorimetry, and the data obtained were analyzed, and we calculated the average Avrami exponent (n) and used the Jeziorny, Mo, and Kissinger methods. The results from all of these methods show that the crystallization mechanism of PA66‐0 mainly consisted of three stages, whereas PA66‐10 mainly consisted of two stages. At the prime stage, both PA66‐0 and PA66‐10 may have had the same crystallization mechanism. When the cooling rates were 15 and 20°C/min, the approximate n suggested that the growth form of the spherulite mode in PA66‐0 may have been complicated, whereas PA66‐10 may have had a one‐dimensional, two‐dimensional space‐extension, circular, diffusion controlled growth. The crystallization activation energies were determined to be 183.2 and 301 kJ/mol for PA66‐0 and PA66‐10, respectively, by the Kissinger method. To further study the influence of the addition of CEPPA on the crystallization behaviors of PA66‐0, the spherulitic morphologies were examined by polarized light microscopy. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41790.     

Kinetic study of the polymerization of ethyl acrylate in an aqueous nitric acid medium

A kinetic study of the aqueous polymerization of ethyl acrylate (EA) was carried out at 30°C in a dilute nitric acid medium with ammonium ceric nitrate (ACN)–n‐propanol (nPA) and ACN–ethanol as redox initiator systems. The ceric‐ion consumption was first‐order with respect to the ceric‐ion concentration with both initiator systems. The formation of complexes between Ce(IV) and reducing agents was observed. The orders with respect to the Ce(IV), reducing agents, and monomer were evaluated for aqueous polymerizations of EA initiated by Ce(IV)–nPA and Ce(IV)–ethanol redox initiator systems. The overall activation energy for the aqueous polymerization of EA was evaluated in the temperature region of 27–40°C with both initiator systems. A kinetic mechanism for the aqueous polymerization of EA initiated by redox initiator systems is presented. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 218–224, 2006     

Complexation of titanium alkoxides with pentenoic acid and allylacetoacetate and their hydrolysis and addition reactions with H‐silanes

Complexation reactions of titanium tetraethoxide [Ti(OEt)₄] and titanium tetra‐n‐butoxide [Ti(OBuⁿ)₄] with 3‐pentenoic acid (PA) and allylacetoacetate (AAA), in a 1 : 1M ratio, were studied in ethanol solution at room temperature. ¹³C‐NMR and FTIR spectra showed that all PA and AAA completely reacted with both titanium alkoxides. Hydridosilane compounds such as triethoxysilane and triethylsilane were added to titanium chelate complexes in a 1 : 1M ratio. The investigation of products by ¹³C‐ and ²⁹Si‐NMR and FTIR showed additions of ? SiH to the C?C double bond. The hydrolysis of titanium–PA and AAA complexes, by water in 1 : 4 ratios, resulted in released PA in an amount of 10% and AAA of 20%. The stability of hydrolyzed products was investigated by ¹³C‐NMR, ²⁹Si‐NMR, and FTIR. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 790–796, 2005     

Toughening of polyamide‐6 with little loss in modulus by block copolymer containing poly(styrene‐alt‐maleic acid) segment

Toughening of polyamide‐6 (PA6) by elastomers without sacrificing the modulus of blends has always been a challenge. In this study, PA6 was modified by poly(styrene‐alt‐maleic acid)‐block‐polystyrene‐block‐poly(n‐butyl acrylate)‐block‐polystyrene tetrablock copolymer (BCP) elastomer. The introduced acid groups in BCP resulted in the size of BCP inclusions down to nanometers in polyamide matrix. 10 wt % of BCP‐modified PA6 blends achieved five times increase in notched impact strength with almost no loss in modulus. Microscopic observations suggested the cavitation of elastomer particles and shear yielding of PA6 matrix to be the major toughening mechanism. This research provides a strategy to toughen polyamides by block copolymers at very low rubber content. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44849.     

The effect of pressure and clay on the crystallization behavior and kinetics of polyamide‐6 in nanocomposites

The crystallization kinetics of polyamide‐6 (PA‐6) and its nanocomposite (PNC) with 2% clay were studied, using a pressure dilatometer (50 MPa to 200 MPa) to follow the volume changes associated with the crystallization process. Isobaric experiments were carried out to evaluate the effect of pressure and clay on melting temperature (T_m) and crystallization temperature (T_a) of PA‐6. The melting temperatures of PA‐6 in the PNC were very close to those of PA‐6 alone at comparable pressures, but the crystallization temperatures in the PNC were lower than those of PA‐6 alone. The materials exhibited two crystallization zones in isothermal/isobaric experiments. The initial zone involved both the γ‐form and the α‐form of PA‐6, while in the latter zone the γ‐form was dominant. The Avrami equation was used to fit the isothermal/isobaric crystallization data. The Avrami exponent n was between 1.0 and 3.2 for the γ‐form of unfilled PA‐6, between 0.9 and 2.6 for the γ‐form in PNC and for the γ‐form of PA‐6 alone, n was between 1.0 and 2.1 and in PNC between 1.2 and 2.6. The Avrami rate constants (K) for PA‐6 and PNC depend on the experimental crystallization temperature as well as pressure. The rate of crystallization under similar conditions was higher for PNC. Infrared studies on compression molded PA‐6 and PNC samples, cooled from melt at different rates, confirm the formation of the γ‐form in the initial stages of crystallization, as well as its transformation into the α‐form at later stages. In the case of PNC, the γ‐form stabilized when the sample was quenched from melt.     

Crystallization studies on linear aliphatic polyamides derived from naturally occurring carbohydrates

The thermal behavior of three series of sugar‐derived polyamides (PA‐nSu) made from the arabinaric, mannaric and galactaric acids, respectively, and α,ω‐alkanediamines containing from 6 to 12 methylene units was investigated by DSC supported by polarizing optical microscopy. Crystallization from the melt under both isothermal and nonisothermal conditions was studied in detail. Melting temperatures of PA‐nSu were found to decay steadily with the length of the polymethylene segment. Data registered from isothermally crystallized samples were analyzed by the kinetics Avrami approach, which revealed that crystallization initiated by combination of instantaneous and sporadically nucleation. Crystallization half‐times indicated that “crystallizability” of PA‐nSu increases with the number of methylenes in the diamine unit and decreases with the length of the carbohydrate‐derived unit. Higher crystallinities were attained for polyamides made of shorter aldaric acids. The relation between thermal data and the configuration of the sugar moiety present in PA‐nSu was discussed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Formulating Pantone colors by unused base inks,formulation software,and a spectrophotometer

Unused base inks that are not going to be used for printing production are considered to be hazardous materials. Their disposal is expensive, and strict environmental regulations should be followed for their disposal. As an alternative, this article describes how spectral data of unused base inks can be gathered and mixed to generate new colors to incorporate them back to print production for small‐volume jobs. In this study, 30 different Pantone colors were selected as target colors. The CIE L*a*b* spectral data of Pantone colors and unused base inks were gathered via a spectrophotometer. A commercial formulation software, based on multiflux theory and CIE L*a*b* color space, was used to formulate ink recipes that contained the base inks. To quantify the performance of ink recipes, they were mixed and printed using an offset printability tester. The CIELAB ΔE*_ab metric, developed by CIE, was used to detect the visual differences between the target Pantone Color and printed colors.     

Permselectivity of polyamide composite membrane modified by solvent

Asymmetric reverse osmosis (RO) polyamide (PA) composite membrane may be modified by means of a solvent‐processing technique into pervaporation (PV) membrane for separating organic aqueous solution. Formic acid, acetic acid, phosphoric acid, hydrochloric acid, phenol, and so forth, better solvents for PA, were selected as the modifying agents in this study. The effect of the modifying conditions (type and concentration of the modifying agent, processing time of membrane in liquid medium) on the sorption of modified membranes was investigated. After the PA composite membrane was treated with 8 wt % acetic acid for 1 h, the swelling rate for water (S_w) increased, whereas that for isopropanol (S_IPA) decreased, compared with that of the nonmodified membrane. The difference between S_w and S_IPA of the membrane treated with acetic acid was greater than that with other modifying agents. The separation factor and flux of the modified membrane were correspondingly maximal when it was used in a PV separating isopropanol aqueous solution. The contact of solvent molecules in liquid medium with polymer chains in the PA membrane and the intranodular chains in the PA membrane tending to diffuse by reptation toward the solvent molecules were the principal causes leading to a change of structure of asymmetric PA composite membrane. The mechanism of changing membrane structure by means of the solvent‐processing technique may better interpret the modification of PA composite RO membrane. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1005–1010, 2004     

Preparation of a structured acrylic impact modifier and its application in toughening polyamide 6

A series of poly(n‐butyl acrylate)/poly(methyl methacrylate‐co‐acrylic acid), i.e., poly(BA/MMA‐co‐AA), core‐shell structured modifiers with different contents of crosslinking agent allyl methacrylate and functional monomer were prepared, and its effects on mechanical properties of polyamide 6 (PA 6) blends were investigated. The modifiers were prepared at a solid content of 50 wt% by a seeded emulsion polymerization. Dynamic light scattering measurement showed that the particle grew without significant secondary nucleation occurring. The morphology was confirmed by means of transmission electron microscopy. Scanning electron microscopy was used to observe the morphology of the fractured surfaces. The dynamic mechanical analysis measurements indicated that the appearance of two merged transition peaks and the magnitude of the loss peak of PA 6 matrix with the addition of PBMA core‐shell modifier in the PA 6/PBMA blends were responsible for the improvement of PA 6 toughness. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers     

Effects of surface modification of carbon nanofibers on the mechanical properties of polyamide 1212 composites

In this study, the effects of carbon nanofiber (CNF) surface modification on mechanical properties of polyamide 1212 (PA1212)/CNFs composites were investigated. CNFs grafted with ethylenediamine (CNF‐g‐EDA), and CNFs grafted with polyethyleneimine (CNF‐g‐PEI) were prepared and characterized. The mechanical properties of the PA1212/CNFs composites were reinforced efficiently with addition of 0.3 wt % modified CNFs after drawing. The reinforcing effect of the drawn composites was investigated in terms of interfacial interaction, crystal orientation, crystallization properties and so on. After the surface modification of CNFs, the interfacial adhesion and dispersion of CNFs in PA1212 matrix were improved, especially for CNF‐g‐PEI. The improved interfacial adhesion and dispersion of CNFs in PA1212 matrix was beneficial to reinforcement of the composites. Compared with pure PA1212, improved degree of crystal orientation in the PA1212/CNF‐g‐PEI (CNF‐g‐EDA) composites was responsible for reinforcement of mechanical properties after drawing. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41424.     

Lipase-Catalyzed Synthesis of Human Milk Fat Substitutes from Palm Stearin in a Continuous Packed Bed Reactor

Structured lipids (SL) with similar fatty acid (FA) composition and distribution to human milk fat (HMF) were synthesized by lipase-catalyzed acidolysis of chemically interesterified palm stearin (IV = 35.6) with mixed FA of stearic acid and myristic acid and FA from rapeseed oil, sunflower oil, and palm kernel oil in a continuous packed bed reactor. Response surface methodology (RSM) was used to optimize the reaction system with three selected parameters, namely residence time, temperature, and substrate molar ratio. The best-fitting quadratic models were obtained for the contents of palmitic acid (PA) and PA at the sn-2 position (sn-2 PA) by multiple regressions and the determination coefficient (R ²) values for the models were 0.9886 and 0.9799, respectively. The optimal conditions generated from the models were as follows: residence time, 2.7 h; temperature, 58 °C; substrate molar ratio, 9.5 mol/mol. Under these conditions, the contents of PA and sn-2 PA were 28.8 and 53.2%, respectively, and other FA observed in the experiments were all within the range of corresponding FA of HMF. The similarity of the product obtained to HMF was evaluated by the cited model. The scores for total and sn-2 FA of the product were 45.2 and 38.4, respectively, and the total score for the product was 83.6, which indicated a high degree of similarity of the product to HMF.