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This study aims to prepare low-cost biomaterials from renewable natural resources (rosin).

Preparation of different biomaterials, ethylene glycol maleic rosin (EGMR), glycerol maleic rosin, pentaerythritol maleic rosin and sorbitol maleic rosin (SMR) esters, then evaluated by stability studies, moisture absorption, swelling index parameters, thermogravimetric analysis and skin irritation studies.

The prepared rosin derivatives had excellent moisture safety, according to the results. From EGMR to SMR, the swelling indices increase.

These rosin biomaterials were used in coating, especially in the field of pharmaceutical coating, and good results were obtained in this study.

As these biomaterials rosin derivatives have excellent moisture resistance, they are recommended for use as coating materials for moisture-sensitive drugs.

There has recently been a lot of interest in researching the effects of rosin derivatives in various drug delivery systems.

This study aims to synthesize polyethylene glycol (PEG)-rosin derivatives from rosin and PEG for the production of solid soldering fluxes. The PEG-rosin derivatives would be water soluble, and the resulting solid soldering fluxes would have reasonable wetting ability when combined with a low-halide-content activator.

This paper presents a synthetic process for PEG-rosin derivatives. The reaction conditions (including catalyst type, catalyst concentration, reaction temperature and PEG type) were optimized for the synthesis of PEG-rosin derivatives. The chemical and physical properties of PEG-rosin derivatives were characterized by Fourier transform infrared spectroscopy, carbon-13 nuclear magnetic resonance spectrometry, differential scanning calorimetry and gel permeation chromatography. The production and characteristics of water-soluble rosin fluxes (WSRFs) were studied according to the standards of the Japanese Industrial Standards (JIS) Committees.

WSRs were successfully synthesized from rosin and PEG using 2 per cent ZnO as a catalyst, with a 2:1 molar ratio of rosin:PEG at 250°C over 9 h. The resulting WSRs were completely soluble in water. As the PEG3000-rosin had the highest melting point (55.2°C), it was chosen for the preparation of the WSRFs. Activators such as succinic acid, glutaric acid, ethylamine hydrochloride and diethylamine hydrobromide were selected for use in the production of the fluxes. It was found that WSRF 09 and WSRF 04 gave the best performance with the lead-free Sn-0.7Cu solder alloy in terms of good solderability, low halide content (less than 1,500 ppm), high insulation resistance and low corrosion. These fluxes were applied to produce solder pastes with Sn-3.0Ag-0.5Cu alloy and they passed the performance tests as expected for solder paste.

Further studies are necessary on large-scale production and to compare the performance of these fluxes to those from conventional water-soluble fluxes currently available in the market. Application of these fluxes on low-temperature solder alloys such as SnZn and SnBi (Ren et al., 2016) worth further study.

The classification of flux systems according to the JIS 3283 standard does not specify PEG-rosin derivatives in the flux; nevertheless, ranking of the flux systems based on the halide content and corrosion properties of activators would be useful information when selecting flux systems for electronics soldering in water-washable applications. The application of these fluxes in solder paste gave very promising results and is worth investigating into more detail, as well as field test.

The purpose of this paper is to see the effect in the properties of shellac on blending with rosin (another natural resin) and study their changes during storage.

Blending of rosin was done at seedlac (semi‐pure lac) stage. Shellac was then prepared by bhatta (Indian country) process, in the form of button lac. Physico‐chemical properties of the blends were studied at regular time intervals following standard procedures.

Improvement in the physicochemical properties of shellac was noticed by blending with rosin to a great extent; less degradation in the properties of blends was observed with storage compared to those of parent shellac.

Because rosin possesses very high fluidity and life under heat, exact value of flow and life under heat of rosin and its blends with shellac having high rosin content could not be determined.

The results give an idea to entrepreneurs, processors and industrialists of how much rosin is to be blended with shellac to bring improvements in its fluidity and life under heat for commercial exploitation, especially for inferior quality of shellac.

Systematic study has been done for the first time, as no quantitative data was available on the changes in the different properties of shellac which take place on blending with rosin.

This study aims to provide control of liquids, especially against water-based ink on the paper and paperboard surface with natural substances, in also practical and greenway.

The paper surface was treated with natural rosin and its derivatives to obtain a hydrophobic effect and to improve printing properties. The oleoresin samples collected from Pinus nigra Arnold and Pinus pinaster Aiton trees in the controlled area and turpentine content removed was by hydrodistillation. The gum rosin (GR), fortified 10% with maleic anhydride (MGR) and esterified with 10% pentaerythritol (PMGR) samples solved in a simply alcohol and sprayed the base paper surface directly with a spray gun. Base paper samples were paperboard, bleached paper and test liner paper. Then, flexo printing was applied and printability properties were measured.

The treatment weights of these paper samples were 1.8 ± 0.5, 1.3 ± 0.5 and 0.7 ± 0.2 g/m², respectively, compared to the base paper. Greater Cobb60 results were obtained from modified rosin samples than unmodified gum rosin-sized paperboards and the PMGR surface treatment reduces Cobb60 values by 20% and MGR treatment reduces 15% comparing to the base sheet. Then, the printing procedure was applied to the surface of the treated materials using a flexo printing system. As a result of the treatment better print density, chroma and print lightness value consumed a less hydrophobic agent and controlling water-based flexo ink on the base paper surface.

The unique aspect of this work was improving the hydrophobicity of the paper surfaces was achieved by spraying with natural rosin and derivatives.

The inhibition of sweet gas corrosion of carbon steel in high pressure CO₂ saturated brine by rosin amine has been studied by weight‐loss, electrochemical polarisation and electrochemical impedance spectrum measurements. The results obtained revealed that rosin amine compound is a good inhibitor. The inhibition efficiency increased with the increase of inhibitor concentration. Rosin amine acts mainly as a adsorptive mixed‐type inhibitor. The adsorption of the inhibitor on the metal surface in high pressure CO₂ saturated brine obey Langmuir isotherm. The adsorption mechanism of inhibitor was both electrostatic‐adsorption and chemisorption.

Rosin‐diethanolamin derivative is used partially or completely as the source of polyol for the formation of recently modified polyesteramid resins. Parameters affecting the reaction between abietic acid (the main constituent of rosin) and diethanolamine, in azeotropic solvent using Dean and Stark apparatus, are studied.

The synthetic reaction of rosin‐modified phenolic resin used as a vehicle for offset inks was studied. The two‐step synthetic process to feed resol by dropping was adopted to control the formation of methylene quinone, which was derived from the dehydration of hydroxymethyl phenol. The methylene quinone could react with rosin and vegetable oil to form dibenzopyran cyclic product by Diels‐Alder reaction. The dibenzopyran cyclic product was favourable for raising the molecular weight and the mineral oil tolerance of the modified resin.

Non‐corrosive rosin fluxes have historically been used for telephone communications assemblies because they provide a measure of reliability even if the flux is not totally removed from the assembly. While cleaning is not always necessary from a reliability standpoint, testing issues, product appearance, operating performance and customer requirements must also be considered when making the decision whether or not to clean. As the electronics industry packages more and more functionality on less and less real estate, soldering yields need to increase in order for the assembly process to remain profitable. This requires not only attention to the product's design for manufacturing but it may also require aggressive fluxes to be used in the assembly process. When aggressive fluxes are employed, the necessity for cleaning is greatly increased. The particular combination of flux and cleaning option depends on product design, process capabilities, end point requirements, and environmental considerations. Pending restrictions on the production and use of chlorofluorocarbons (CFCs), and the potential for tighter controls on chlorinated solvents and aqueous detergent effluents, are certain to add to the cost of standard processes. For these reasons alternative cleaning processes have been explored. The evaluation and subsequent use of water soluble flux with ‘water only’ cleaning, terpene cleaning of rosin flux residues, low solids flux ‘no‐clean’ wave soldering and ‘no‐clean’ assembly using reflowed rosin based solder pastes within AT&T are reviewed. A user's assessment of aqueous and semi‐aqueous cleaning is presented which indicates that there are acceptable alternatives to CFCs.

Visible surface residues, commonly referred to as white residues, on soldered printed circuit assemblies are a very common but intermittent and unpredictable problem. Such residues, which are insoluble in normal solvents, are generally a rejectable condition. The chemistry of the deposition of white residues is complex; the deposits themselves are of a number of types and origins, and their incidence is associated with both materials and process parameters. This paper attempts to identify the different causes of the problem and suggest ways in which avoidance or removal is possible.

Various rosin‐modified polyesteramide resins are formulated and evaluated for their insecticidal activity. Five kinds of pyrethroid and organophosphorus insecticides with trade names Neo‐Pynamin Forte, Gokilaht, Neo‐Pynamin, Sumithrin and Cyanox are studies. American Cockroaches (Periplaneta americana) are the target insect.