RU2633717C1 - Phenolformaldehyde binder and fibreglass on its basis - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: fibreglass includes a prepreg that uses fibreglass and a phenolformaldehyde binder that contains a resole phenolformaldehyde resin, which uses a highly concentrated condensation product of phenol and paraformaldehyde, an organic solvent used as acetone, and a novolac phenolformaldehyde resin. In addition, the binder further comprises pyrogenic silica and polycyclic amine, which is used as urotropine.

EFFECT: reducing the heat generation during combustion, increasing the mechanical properties, viscosity control and reduction of gel time.

3 cl, 3 tbl, 6 ex

Description

The present invention relates to fiberglass, phenol-formaldehyde binders and composite materials based on them, is intended for the manufacture of fireproof products, such as: low pressure ducts of the air conditioning system in aircraft; interior materials of passenger aircraft; in shipbuilding, automotive industry and railway transport, as well as for the manufacture of radio-transparent products.

Materials for the manufacture of fireproof products (low-pressure ducts for air conditioning in aircraft; interior materials of passenger aircraft) according to the requirements of international and Russian standards of airworthiness (NLGS and FAR) must be slow-burning, slightly smoky and have low heat during combustion.

It is known that phenol-formaldehyde resins modified with flame retardants are used as binders for non-combustible materials: phosphorus, nitrogen, antimony compounds, halogen-containing compounds, mineral flame retardants (JP 3231955 B2, G01L 3/10, publ. 26.11.2001 and JP 4159357 B2, A61M 25/25 00, published on October 1, 2008).

The disadvantages of these materials are the multicomponent and toxicity of binders, determined by the toxicity of the flame retardants used and the high (up to 30%) content of free phenol.

Known non-combustible composite material for interior decoration of interiors of passenger aircraft and other vehicles based on phenolic binders and fiberglass fillers (WO 0247906 Al, B32B 25/04, publ. 20.06.2002).

Known fire-resistant low-toxic fiberglass based on glass filler and a polyester binder, in which aluminum hydroxide was introduced to reduce flammability and smoke emission (SU 1552518 Al, B32B 27/36, publ. 10.11.1995).

The disadvantage of the above non-combustible composite materials is the increased value of heat during combustion.

The closest analogue adopted for the prototype (RU 2333922 C1, C08L 61/10, publ. 09/20/2008) is a phenol-formaldehyde binder comprising a resol phenol-formaldehyde resin, which contains a highly concentrated phenol-paraformaldehyde condensation product with a water content of not more than 10% and non-volatile substances not less than 86%, an organic solvent, which is used as acetone, and novolac phenol-formaldehyde resin in the following ratio of components, wt. hours:

rezol phenol-formaldehyde resin one hundred novolac phenol-formaldehyde resin 33-100 acetone 33-130

and also a prepreg, including the above binder and reinforcing filler, which contains fiberglass, in the following ratio, wt. hours:

binder 20-80 fiberglass 28-48

The disadvantages of the binder and the prepreg of the prototype is the increased gelation time and unregulated viscosity of the binder, which in particular negatively affects the adhesion of the skin and honeycomb core in three-layer structures.

The technical task of the invention is the creation of a fast-curing phenol-formaldehyde binder and fiberglass based on it.

The technical result of the invention is to reduce heat during combustion, increase mechanical properties, adjustable viscosity and reduce gelation time.

To solve the technical result, a phenol-formaldehyde binder is proposed, including rezol phenol-formaldehyde resin, which contains a highly concentrated product of the condensation of phenol and paraformaldehyde, an organic solvent, which is used as acetone, and novolac phenol-formaldehyde resin, and it additionally contains pyrogenic silica and as which urotropine is used, in the following ratio of components, wt. hours:

rezol phenol-formaldehyde resin 25-90 novolac phenol formaldehyde resin 6.25-22.5 acetone 6.25-22.5 fumed silica 0.9-3.2 urotropin 0.5-1.8

In addition, claimed fiberglass, including a reinforcing filler, which is used as a fiberglass, while containing the aforementioned phenol-formaldehyde binder in the following ratio, wt. hours:

phenol formaldehyde binder 81-110 fiberglass 85-180

Preferably, the fiberglass further comprises a monolayer from 0.075-0.18 mm. Such a monolayer is necessary for the manufacture of thin-walled elements.

When using the inventive fast-curing phenol-formaldehyde binder in combination with a reinforcing filler, fiberglass was obtained with a reduced gel time of 1-5 minutes and an adjustable viscosity of 10 to 30 seconds, with a reduced molding time of 5 to 40 minutes at a molding temperature of 90 to 160 ° C, s monolayer from 0.075 to 0.18 mm.

The use of rezol phenol-formaldehyde resin in combination with novolac resin, pyrogenic silica and polycyclic amine with the stated ratio of components allows to obtain a fast-curing binder, which forms a polymer matrix with high strength properties and low heat during combustion upon curing at a temperature of 90-160 ° С.

Another advantage of the present invention is the adjustable viscosity of the binder due to the introduction of pyrogenic silica into its composition and the reduced gelation time due to the introduction of a polycyclic amine, which, in turn, prevents the binder from flowing out when loading a prepreg using glass fabric and phenol-formaldehyde binder.

The high curing rate of the claimed phenol-formaldehyde binder (due to the introduction of a polycyclic amine) at temperatures up to 160 ° C is combined with high viability, which provides prepreg, which uses fiberglass and the claimed binder, a shelf life of at least 4 months.

As rezol phenol-formaldehyde resin in the claimed invention used a highly concentrated condensation product of phenol and paraformaldehyde with a water content of not more than 10%, non-volatile substances - not less than 86%, viscosity not more than 13000 mPa⋅s at a temperature of 20 ° C, gelation time 300-720 s and the mass fraction of free phenol is not more than 11% of the FS-117 brand according to TU 2221-001-35907133-01.

As a novolac phenol-formaldehyde resin, it is most preferable to use resins according to GOST 18694-80, for example, grades SF-010, SF-014, etc.

As fumed silica, it is preferable to use silica grade A-380 according to TU U 24.1-31695418-002.

As a polycyclic amine, it is necessary to use urotropin according to GOST 1381-73.

As a reinforcing filler can be used fiberglass brands T-64 (TU 5952-009-16319666-98) and T-15 (P) -76 (TU 6-11-491).

The binder compositions are shown in table 1, the properties of the binder are in table 2, the properties of fiberglass in table 3.

Examples of implementation

Example 1

12.5 wt. including novolac phenol-formaldehyde resin SF-014 was dissolved in 12.5 wt. including acetone, was added 50 wt. including rezol phenol-formaldehyde resin FS-117 and was stirred until a homogeneous solution. In the resulting binder solution was added 1.1 wt. including polycyclic amine, which was used urotropine, and stirred until a homogeneous solution. Then added 2 wt. including pyrogenic silica grade A 380 and mixed until a homogeneous solution. Determined the conditional viscosity, the content of non-volatiles, the gelation time, the water content and free phenol.

Example 2

6.25 wt. including novolac phenol-formaldehyde resin SF-014 was dissolved in 6.25 wt. including acetone, was added 25 wt. including resol resin FS-117 and mixed until a homogeneous solution. In the resulting binder solution was added 0.5 wt. including polycyclic amine, which was used urotropine, and stirred until a homogeneous solution. Then added 0.9 wt. including pyrogenic silica grade A 380 and mixed until a homogeneous solution.

Determined the conditional viscosity, the content of non-volatiles, the gelation time, the water content and free phenol.

Example 3

22.5 wt. including novolac phenol-formaldehyde resin SF-014 was dissolved in 22.5 wt. including acetone, was added 90 wt. including resol resin FS-117 and mixed until a homogeneous solution. In the resulting binder solution was added 1.8 wt. including polycyclic amine, which was used urotropine, and stirred until a homogeneous solution. Then added 3.2 wt. including pyrogenic silica grade A 380 and mixed until a homogeneous solution.

Determined the conditional viscosity, the content of non-volatiles, the gelation time, the water content and free phenol.

Example 4

A binder was made according to example 1.

Fiberglass includes a prepreg, which used 85 wt. including fiberglass brand T-64, which was impregnated with 81 wt. including the obtained binder. The prepreg was dried at a temperature of 100-160 ° C. To obtain fiberglass, a package of 18-24 layers of prepreg was collected and formed by vacuum molding at a temperature of 90-160 ° C and a pressure of 0.2-0.6 atm.

Example 5

A binder was made according to example 1.

Fiberglass includes a prepreg, which included 100 wt. including fiberglass brand T-15 (P) -76, which was impregnated with 100 wt. including the obtained binder. The prepreg was dried at a temperature of 100-160 ° C. To obtain fiberglass, a package of 10-14 layers of prepreg was collected and formed by vacuum molding at a temperature of 90-160 ° C and a pressure of 0.2-0.6 atm.

Example 6

A binder was made according to example 1.

Fiberglass includes a prepreg, which used 180 wt. including fiberglass brand T-15 (P) -76, which was impregnated with 110 wt. including the obtained binder. The prepreg was dried at a temperature of 100-160 ° C. To obtain fiberglass, a package of 10-14 layers of prepreg was collected and formed by vacuum molding at a temperature of 90-160 ° C and a pressure of 0.2-0.6 atm.

From the data of table 2 it follows that the inventive phenol-formaldehyde binder is characterized in that it has a reduced viscosity and a reduced gelation time, which, in turn, prevents the binder from flowing out when loading the prepreg, which uses fiberglass and the claimed phenol-formaldehyde binder, in heated equipment.

The prepreg, which uses fiberglass and the claimed phenol-formaldehyde binder, has a high viability, which provides it with a shelf life of at least 4 months at a storage temperature of 2 to 5 ° C.

From the data of table 3 it follows that when using the inventive phenol-formaldehyde binder in combination with a reinforcing filler can be obtained: fiberglass - with reduced heat during combustion, with increased mechanical properties (1.5-2 times) compared with the prototype.

The fiberglass obtained according to the present invention fully satisfies the requirement of aviation regulations (Part 25, Appendix F) for heat generation, which will increase flight safety, and can be used for the manufacture of fireproof products, such as low pressure ducts, air conditioning systems in aircraft, as well as interior materials passenger aircraft, shipbuilding, automotive and rail. The use of the claimed binder will reduce the labor and energy intensity of production, eliminate the use of imported and severely deficient domestic raw materials.

Claims (5)

1. Phenol-formaldehyde binder, including resole phenol-formaldehyde resin, which contains a highly concentrated product of the condensation of phenol and paraformaldehyde, an organic solvent, which is used as acetone, and novolac phenol-formaldehyde resin, characterized in that it additionally contains pyrogenic silica and polycyclic amine which uses urotropin, in the following ratio of components, parts by weight: rezol phenol-formaldehyde resin 25-90 novolac phenol formaldehyde resin 6.25-22.5 acetone  6.25-22.5 fumed silica 0.9-3.2 urotropin 0.5-1.8. 2. Fiberglass, including prepreg, which is used fiberglass, characterized in that it contains phenol-formaldehyde binder according to claim 1 in the following ratio of components, parts by weight: phenol formaldehyde binder 81-110 fiberglass 85-180. 3. Fiberglass according to claim 2, characterized in that it further comprises a monolayer of 0.075-0.18 mm