Search results

1

Żółknięcie żywic epoksydowych

100%

Ciabach J.

Ochrona Zabytków

|

1989

|

issue 1

36-38

EN

The biggest shortcoming of epoxide resins is their yellowing under the effect of light. The resins which turn yellow easily are mainly the cheapest, universally available and widely applied epoxide resins obtained from dian and epichlorohydrin. Until now chemists have not been able to establish the mechanism of their yellowing, although it is well-known that this process depends largely on a chemical structure of resins, their kind and quantity of auxiliary substances (dissolvents, softeners, accelerators, hardening agents and conditions of hardening). A vast number of such products is offered on the market, some of which show very high resistance to yellowing, whilst the resistance of others is very low. The article mentions products with exceptionally high resistance to yellowing under the effect of temperature and also describes light fastness of some epoxide compounds made by Ciba-Geigy. Attention has been paid to the fact that improper hardening reduces light fastness of hardened resins.

2

Badania nad uelastycznieniem żywicy Epidian 5

86%

Soldenhoff B.

Ochrona Zabytków

|

1976

|

issue 2

110-113

EN

The present report deals with the properties of solutions of the epoxy resins when they ace used to reinforcement of the damaged historical objects. Besides the advantageous qualities such as low viscosity and chemical and biological resistance, they have also negative features, especially orispness, which has essential meaning in case of reinforcement of a very damaged wooden surface. Before they are used epoxy resins must undergo the process of making elastic. It consists of the so-called internal and external plasticization. In the first case we add to the resin chemical compounds capable of reacting with it, like: polysulphides, polyesters, acid anhydrides. In the latter case, however, we add substances not reacting with it, e.g. dibutyl phthalate, which is one of the constituents of the composition called in Poland Epidian 5. Epidian 5, modified by dibutyl phthalate, underwent narrow tests in view of being used in restoration works consisting of the reinforcement of wood. It has been found, as the result of the research, that dibutyl phthalate does not cause any visible destructive changes in hardened resin films but gives it elasticity and, what is more, does not make the wood swell. Optimum proportion is 20 per cent of dibutyl phthalate and 80 per cent of resin. With Epidian 5 a great number of historical wooden carvings has been preserved.

3

"Monumentum", T. IV, 1969 : [recenzja]

72%

Lenard B.

Ochrona Zabytków

|

1970

|

issue 4

328-329

Refine search results

3 Ochrona Zabytków

1 Ciabach J.

1 Lenard B.

1 Soldenhoff B.

1 1989

1 1976

1 1970

Żółknięcie żywic epoksydowych

Badania nad uelastycznieniem żywicy Epidian 5

"Monumentum", T. IV, 1969 : [recenzja]