One-pot catalytic synthesis of urea derivatives from alkyl ammonium carbamates using low concentrations of CO2

To reduce anthropogenic carbon dioxide (CO2) emissions, it is desirable to develop reactions that can efficiently convert low concentrations of CO2, present in exhaust gases and ambient air, into industrially important chemicals, without involving any expensive separation, concentration, compression, and purification processes. Here, we present an efficient method for synthesizing urea derivatives from alkyl ammonium carbamates. The carbamates can be easily obtained from low concentrations of CO2 as present in ambient air or simulated exhaust gas. Reaction of alkyl ammonium carbamates with 1,3-dimethyl-2-imidazolidinone solvent in the presence of a titanium complex catalyst inside a sealed vessel produces urea derivatives in high yields. This reaction is suitable for synthesizing ethylene urea, an industrially important chemical, as well as various cyclic and acyclic urea derivatives. Using this methodology, we also show the synthesis of urea derivatives directly from low concentration of CO2 sources in a one-pot manner.

Heat-induced changes in cellulose nanocrystal/amino-aldehyde biocomposite systems

Cellulose nanocrystals (CNCs) were extracted from natural cellulosic fibres such as bleached cotton and flax with a controlled multi-step sulphuric acid hydrolysis. From the aqueous suspensions of CNCs, the biocomposite films were prepared by casting and evaporation, with an amino-aldehyde (AA) compound in a wide concentration range from 0 to 30%. The AA compound (dimethylol dihydroxy ethylene urea) was considered both as a cross-linker of the CNC and as a matrix polymer for the CNC-reinforced composite system. Two series of films were prepared using different polyols such as sorbitol and glycerol as plasticizers to improve tractability. Heat treatment of the films was performed at elevated temperatures ranging from 140 to 200 °C for 10 min. Results clearly proved that besides temperature, the factors affecting the response of CNC-based nanocomposites to heat treatment were the source of cellulose, the type of plasticizer and the amount of cross-linking agent. Films based on flax–CNC and plasticized with glycerol showed a higher increase in yellowness and a more significant decrease in haze than those derived from cotton–CNC and plasticized with sorbitol, respectively. The cross-linking agent (AA) had a moderating effect on the heat-induced changes of properties. Furthermore, thermal gravimetric analysis (TG) of films revealed that thermal stability of the CNC films improved considerably when AA was added and cross-linking occurred. The increase in Tmax was more significant for the flax–CNC films (from about 230 to 290 °C) than for the cotton–CNC ones (from about 250 to 280 °C).

Pengaruh Konsentrasi Senyawa Dihidroksi Etilena Urea (Akrofik NZK) Pada Proses Finishing Kain Kapas 100% Dengan Metode Pemanas Awetan Suhu Rendah (Low Curing) Terhadap Stabilitas Dimensi, Kekuatan Sobek Dan Kekuatan Tarik

The process of producing uniforms or shirts made of 100% cotton which has a pattern of weaving or printing is very much in demand, especially in Indonesia with a tropical climate which is suitable for wearing clothes made from cotton. The need for 100% cotton fabric needs both domestically and abroad made the textile companies intensely innovate because of the connection with the quality of the cotton fabric to meet market standards and in accordance with consumer desires. There are several factors that usually affect the quality of a fabric, including dimensional stability, tensile strength and tensile strength. Anti-creasing enhancements are a form of resin refinement application intended to improve the wrinkle-resistant properties of cellulose fabrics. The purpose of this study was to determine the optimum conditions that can be achieved from the addition of anti-tangle resin substances (Acrylics NZK) to the physical properties of the fabric. The resin used was an anti-creasing resin with the trade name Ackfik NZK (Dihydroxy Ethylene Urea) using a temperature of low heating (Curing 130 C) and a concentration variation of 80, 90. 100,110 g / l. The results showed the optimum conditions achieved in this experiment were the concentration of anti-creasing agent 100g / l with a heating temperature of 130 C obtained a formaldehyde-free content of 55.80 ppm, dimensional stability of 3.2% wariness of 2.4% warp and towards the feed , tear strength of 0.640 kg of cloth towards the warp of 0.625 kg in the direction of feed, Pull strength of fabric 24.43 kg in the direction of warp 11.86 kg in the direction of feed.

Influence of crosslinking agent on the effectiveness of flame retardant treatment for cotton fabric

In this study, the commercial organophosphorus compound Pyrovatex CP New was used as a flame retardant for cotton fabric. Citric acid and a modified dihydroxy ethylene urea (DHEU) labelled Knittex FFRC were used as crosslinking to increase the flame-retardant laundering durability of treated cotton fabric. There have been some studies showing that Chitosan has the potential to improve flame retardancy and laundering durability of flame retardant treated cotton fabric. Thus, Chitosan, which has the molecular weight of 2.600 (water soluble) and the deacetylation degree of approximately 75%, is added to finishing solution for flame retardant treatment of cotton fabric. The padding-drying-curing method was used in this study. After treatment, all samples were examined to determine the chemical absorption level. The 45° flammability test characteristics and LOI value of untreated and treated samples after different number of washing cycle were determined to assess the flame retardancy of the treated fabric and its laundering durability. In addition, to assess the impact of this treatment on the mechanical strength and ecology of the fabric, the tensile strength and free formaldehyde content of the treated fabric were also evaluated

Application of Sericin on Polyester Fabric

Sericin is a natural protein which is removed from silk in a process called degumming. In India, 250-300 tons of sericin is extracted per year and goes as waste, it has wide range of application because of its properties like antioxidant, antibacterial, UV resistant, anticoagulant and moisture retention capacity. This paper is concerned with the application of sericin on polyester fabrics using cross linking agents like di-methylol di-hydroxy ethylene urea (DMDHEU) and glutaraldehyde. The Polyester fabrics are pretreated with sodium hydroxide (NaOH) and low temperature plasma (Oxygen gas). This pretreated sericin applied polyester fabrics show the better improvement in the wicking (moistureabsorbency) and good dye uptake properties on acid dyed fabric and it will be used for medical application.

The Composite Catalysts Used for Cotton Denim Resin Wrinkles Setting

Severe strength loss is the most important problem for denim wrinkle-setting resin finishing. N,N-dimethylol 4,5-dihydroxy- ethylene urea (DMDHEU) resin、composite catalyst, baking time and temperature were used as four important factors in experimental design by central lab. The significant influence and the optimum condition achieved by analysis four factors and regression analysis. In contrast to traditional catalyst magnesium chloride, under optimum condition employed by composite catalyst 20.61(g/L), resin 143.08(g/L), baked at 129.4°C for 18.0 min, the strength loss of treated fabric reduced by more than 12%.