Urea-Formaldehyde and Melamine-Formaldehyde Condensations

Resin MUF yang boleh larut dalam air digunakan dengan meluas sebagai bahan pelekat dalam industri kayu, teknologi salutan, industri kertas dan merupakan bahan utama dalam penghasilan barangan dapur plastik. Sifat resin yang berbeza diperlukan dalam aplikasi yang berlainan. Sifat–sifat resin ini dipengaruhi oleh beberapa faktor iaitu nisbah mol antara formaldehid dengan melamina/urea pada setiap peringkat tindak balas dan bilangan peringkat tindak balas di mana sebatian amino ditindak balaskan. Sifat–sifat resin yang penting ialah kestabilan resin, kelarutan dalam air yang tinggi dan tempoh pengerasan yang pendek. Kajian lepas telah menghasilkan resin MUF dengan sifat–sifat ini, walau bagaimanapun ia tidak mempunyai kandungan melamina dan urea yang mencukupi, untuk menyeimbangi kos dan prestasi. Selain itu haba juga diperlukan untuk membantu memendekkan tempoh pengerasan resin. Dalam kajian ini, kesan perubahan formula ke atas sifat–sifat resin seperti kestabilan resin, kelarutan dalam dan tempoh pengerasan pada suhu bilik dikaji. Keputusan menunjukkan bahawa kestabilan resin meningkat apabila bilangan peringkat tindak balas dan kandungan melamina meningkat. Walau bagaimanapun tempoh pengerasan turut dipanjangkan. Formula ini mempunyai kandungan melamina dan urea yang mencukupi, di mana ia berkos rendah berbanding resin melamina-formaldehid (MF), tapi dengan prestasi yang baik. Kata kunci: Melamina-urea-formaldehid (MUF); urea; melamina; formaldehid MUF resin is widely used as an adhesive in wood industries, coating technology, paper industries and a main material in kitchenware production. In different application, various MUF resin properties are required. The MUF resin properties are affected by several factors, for example mole ratio of formaldehyde to melamine/urea at each reaction stage and number of reaction stages where the amino compounds are reacted. Previous researches have developed MUF resin with these properties, however the formulation lack sufficient amount of melamine or urea to balance the cost and performance. Furthermore, shorter curing period could only be obtained with the help of external heat. In this research, effects of formula variation on resin properties such as resin storage stability, solubility in water and curing period at room temperature are investigated. The results showed that in 3-reaction stage of MUF resin process, the ratio of formaldehyde to urea/melamine in each reaction stage has caused significant increases in MUF resin curing period, solubility in water and resin storage stability. These formulations contains sufficient amount of melamine and urea, which lowered the cost and yet maintaining good performance as compared to melamine–formaldehyde (MF) resin. Key words: Melamine-urea-formaldehyde (MUF); urea; melamine; formaldehyde

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Modification with Melamine Formaldehyde and Melamine-Urea Formaldehyde Resin to Improve the Physical and Mechanical Properties of Wood

BioResources ◽

10.15376/biores.12.1.586-596 ◽

2016 ◽

Vol 12 (1) ◽

Author(s):

Suat Altun ◽

Veysel Tokdemir

Keyword(s):

Mechanical Properties ◽

Urea Formaldehyde ◽

Physical And Mechanical Properties ◽

Urea Formaldehyde Resin ◽

Formaldehyde Resin ◽

Melamine Formaldehyde

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Possibilities of affecting the chemical resistances of the coatings formed by reaction of amino resins with alkyd resins

Pigment & Resin Technology ◽

10.1108/03699420210412566 ◽

2002 ◽

Vol 31 (1) ◽

pp. 27-32 ◽

Cited By ~ 7

Author(s):

P. Kalenda ◽

A. Kalendová

Keyword(s):

Chemical Stability ◽

Alkyd Resin ◽

Castor Oil ◽

Film Formation ◽

Urea Formaldehyde ◽

Melamine Formaldehyde ◽

Coating Films ◽

Alkyd Resins ◽

Solid Films

The paper deals with the mode of film formation from urea–formaldehyde and melamine–formaldehyde resins combined with alkyd resin based on castor oil‐modified alkyd. The properties of hardened coatings (such as hardness, chemical stability, and adhesion to substrate) were followed in dependence on the ratios of reaction components. An apparatus was built for measuring the formaldehyde emissions escaping from the solid coating films. The determination was performed by the pararosaniline method. The addition of imidazolidine in a concentration up to 10 per cent can reduce the emissions of formaldehyde escaping from the solid films to a considerable amount.

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