DE2534451A1 - RESIN-BASED ADHESIVES OR BINDERS AND ADHESIVE, BINDING AND COATING PROCESSES AND MOLDED BODY PRODUCTION - Google Patents

Description

Tn If patent attorneys:

IEDTKE - DÜHLING "IVlNNE Dipl.-Irg. Tiedtke

Dipl.-Chem. Bühling Dipl.-Ing. Chins

2534451 ⁸ Munich 2, P.O. Box 202403

Bavariaring 4

Tel .: (0 89) 53 96 53 - 56

Telex: 5 24845 tipat

cable: Germaniapatent Munich

B 6753 / ICI case

B. 27207/27503

1 . August 1975

Imperial Chemical Industries Limited London, UK

Resin-containing adhesives or binders and adhesives, binders and coating processes as well as molding production

The invention relates to liquid adhesives or binders comprising a thermosetting resin, in particular urea-formaldehyde (UF) resin, melamine formaldehyde (MF) resin or a mixture of these resins.

Commercially available cold-curing liquid UF resins that are cured with acids or acid generators are available as Glue, for example for cellulosic or other porous materials and for the treatment of paper and Textiles have been widely used to impart useful modified properties thereto. However, since they shrink extraordinarily strongly and become very brittle during curing, they show only poor adhesion on smooth, non-cellulosic surfaces and, in

V 609810/1003

When poured in a thick layer, they quickly suffer network-like cracks (i.e. they quickly disintegrate with cracks, caused by the internal stresses developed during the hardening process). In To a certain extent, this cracking can be caused by the addition of fillers or by hardening with formic acid or partial esterification of the resin can be reduced with alcohols.

It has now been found, however, that common, commercially available water-soluble UF resins such as "AEROLITE 300" (from Ciba-Geigy Ltd) mixed with polymer latex can be hardened to thick, waterproof masses, which are much less susceptible to cracking and excellent Show adhesion to surfaces, but not for the UF resins themselves are suitable. These resin / latex mixtures were tested and, for example, as adhesives or binders, as waterproof Coatings for a variety of surfaces and as binders for particulate and fibrous materials such as fiberglass, asbestos, etc. found useful. Furthermore, these resin / latex mixtures can be used with or without additives of particulate or fibrous reinforcement materials to form blocks, panels or tiles or wansformform compared to conventional UF resin phone bodies are extremely tough or strong and do not subsequently disintegrate with cracking. Such a shaping can after a partial drying and / or The hardening of the resin proceeds.

60 9810/1003

" ³ " 2 b 3 4 4 b Ί

Neoprene latex, for example, is alkaline (with a pH of about 11 to 13) and is precipitated by acidification or contact with various substances such as ammonium or calcium salts. It is, however, compatible with aqueous UF-resin solutions, and it has now been found that stable liquid mixtures can be prepared containing 5 to 95 wt.% (For example 20 to 80%) of latex mixed with 95 to 5 Gev.% (For example 80 up to 20% by weight) UF resin solution. Such mixtures remain stable for a few days at room temperature and then gel slowly, but this gelation can be further delayed by adding conventional stabilizers to the mixture. Such mixtures are useful when an alkaline (or at least neutral) binder is desired and when rapid curing is neither particularly required nor desired, such as when making, pouring or applying cement and concrete mixes.

However, it has also been found that such UF / latex mixtures (for example with formic acid solutions such as a 10% solution of 85% by weight formic acid in water) can be acidified to the point where the latex does not yet precipitate and the mixtures are still fluid and homogeneous; However, these acidified mixtures now gel at room temperature in times of a few (about 2 or 3) minutes to about an hour, which makes them suitable for potting in the form of blocks, panels, tiles or the like.

6 0 9810/1003

253U51

same, for the coating of surfaces, for the connection of similar or different surfaces or surface materials with one another and for the bond of particulate or fiber materials makes it very suitable.

According to the invention, a liquid adhesive or binding agent is thus provided which contains 5 to 95 % by weight (for example 20 to 80 %) of a polymer latex and 95 to 5% by weight (for example 80 to 20 %) of an aqueous solution of a thermosetting resin, in particular of Urea formaldehyde (UF) resin, melamine formaldehyde (MF) resin or a mixture of such resins.

The invention also encompasses a liquid adhesive or binder of the type just described, which additionally contains a resin curing catalyst in an insufficient for the precipitation of the latex So that the material is still liquid and homogeneous.

According to the invention, there are also methods for coating surfaces and connecting objects with similar or dissimilar surfaces or surface materials to one another, bonding of particle or fiber materials Manufacture of moldings by producing a binder mixture with or without particulate or fibrous Reinforcement material and potting of the mixture are each provided in the manner described in more detail below, wherein the coating, adhesive or binding agent

is a composition or mixture as described in one of the two immediately preceding paragraphs became.

The resin curing catalyst is preferably an acid or acid-generating substance, particularly formic acid. The polymer latex is preferably a neoprene, for example "Neoprene 400", but it can also be through any other synthetic or natural polymer latex or an aqueous emulsion based on acrylic polymers are formed.

It has also been found that the liquid binders according to the invention can be used for certain applications described below by mixing with an alkali silicate, in particular sodium silicate, in proportions of 5 to 95% by weight (for example 20 to 80 %) silicate to 95 to 5% by weight (for example 80 to 20 %) of the combined resin and latex ^{1 can be} modified and improved. The number of possible variations with the three basic components is considerable. As well as different proportions of the constituents, different resin qualities, silicates and types of latex can be used. It has been found that wide variations in pot life and adhesive or binding capacity can be achieved. Possible combinations are summarized in four groups, which are given in the table below. Some of the uses include the addition

b ü 9 H 1 Ü / 1 η Π 7

of cement or sand or clay as a filler, as follows is described:

Ka)
(b) Head- *
component lesser
component sour or
alkaline Applications 2 (a)
(b) U / F
U / P latex
Latex +
silicate alkaline/
neutral
alkaline/
neutral Modification of
Cement; primer
for StahibeSchich
with or
without added cement 3 (a) U / P
U / P latex
Latex +
silicate angry
angry widespread use
applications for coating
connections and connections
fertilize; good water
strength; with
Filler (however
not with cement)
applicable 4 (a)
0>) silicate U / F +
latex preferably
se pissed off very cheap glue
or connection
system latex
latex U / F
U / F +
silicate preferably
angry
preferably
angry improved adhesion
of latex; cheap
re systems as la
tex alone

* Correspondingly more than 50% by weight of the total in one Two-component system. In a three component system, the main component forms the highest percentage by weight of the three components, but not necessarily more than the combined weight percent of the two subordinate components.

The functions of the components are summarized below. ALI these materials are binders, however

B09810 / 1003

the mixtures better than the individual components.

Urea formaldehyde
resin

may contain high polymer components that precipitate rapidly with silicates Result in bonding and hardening;

improves the water resistance of SiIicat (if present)

confers acid resistance

makes the system tough or firm, thereby increasing the strength, adhesion and service life the bond is improved;

enables the systems to be used as coatings and coatings;

accelerates and improves the hardening of UF resin, but causes, in excess used a precipitation of silica or coagulation of latex.

silicate

^ forms an alkaline medium from which
High polymer components fail;

makes the system cheaper

gives high temperature properties

Some examples of possible uses of the binders according to the invention are given below:

1. Surface coatings for wood, wood particle or chipboard, urea-formaldehyde foam, stiff synthetic foam laminates, plasterboard, stucco or Model plaster products;

2. Binding or connection of reinforcing surface layers such as paper, glass, fabric or fabric, metal or panels, panels, etc. made from the above materials;

3. Glue for joining wood, chipboard and the like Materials with each other (provided that at least one of the materials is sufficiently porous to allow moisture to escape);

4. Acid-resistant coatings for stones and bricks;

5. Acid-resistant sand, clay, plaster of paris, plaster of paris or other fillers containing mortars for joints and joints as well as seals or covers;

6. Forming of acid-proof tiles containing sand, clay or other reinforcing fillers;

7. acid-resistant coatings for concrete, especially in concrete silos; the concrete is first coated with the neutral binder (as a primer) and then with the acidified binder;

8. Coatings on or on reinforced concrete pipes;

9. Production of tubes or rolls by suitable conventional methods such as winding of paper, thread, fibers or other reinforcing materials, impregnated with the binder, to paper tubes or other temporary or permanent support or by centrifugally spinning the binder inside a Shape or similar method. The binder can be filled and / or reinforced as suggested above.

10. binding of vermiculite into blocks;

fc09810 / 1003

11. Determination of the bristles for the brush or paintbrush production (a traditional application for epoxy resins);

12. as a moisture protection material, e.g. in concrete floor, preferably with sand, clay or other reinforcing materials;

13. Coatings for paper to get high gloss, moisture-proof To achieve papers;

14. Coatings for cardboard, e.g. in the manufacture of insoles for shoes;

15. Binding of emery papers;

16. Bonding of seals;

17. Binding of non-woven fabrics including the Treatment of asbestos fibers to remove fine

prevent short fibers;

18. Binding of particulate materials such as sand or coal dust for the production of casting mold cores or pressed carbon or briquettes;

19. sand-filled mortars for use as rough plaster with protrusions;

20. Combination of fresh concrete with old;

21. Rapid wood on wood glue;

22. Rapid adhesive for corrugated sheets, paper laminates, laminate boards;

609810/1003

23. improved concrete j the addition of an inventive The binder leads to the filling of gaps and increases the mechanical strength;

24. Concrete and steel connection - cement can be added to the binding agent;

25. improved building plaster; some or all of the water used for the slurry can pass through an inventive binder can be replaced. This greatly increases the mechanical strength and imparted weather resistance to the gypsum products.

26. Roofing laminates and siding panels for building purposes;

27. Concrete facing and shuttering walls as well as permanent cladding and other shaped profiles.

Since the liquid binders according to the invention are in most cases not marketed as such, but to be prepared at the time of use or shortly before use, it is clear that the invention can also be prepared separately the binder comprises wherein the components of the liquid binder are kept separate until use whereupon the contents of the separate packs are mixed together.

example 1

The following preparations were made (the quantities given in; parts by weight):

609010/1003

comparative
mixture _ "Aerolite 300" 100 "Neoprene 400" * 0 10 % ants
acid solution 10

k 1 6

100 100 100 100 100 100 5 10 20 25 100 200

11.5 13 16 17.5 AO 70

* from DuPont de Nemours.

Blocks made from the above liquid mixtures by pouring into Petri dishes gave the following results:

Comparative mixture Cracks and cracks occurred in 3 days

Room temperature on;

Cracks appeared in about 5 days

Room temperature;

very slight cracking occurred after 9 days

at room temperature;

after 7 months at room temperature

no cracking found;

after 7 months at room temperature

no cracking found;

no cracking, but some

Shrinkage;

the latex was made by the formic acid

precipitated from solution, but eventually became a solid, non-cracked block obtain.

£ 09810/1003

Another mix # 7

"Aerolite 300" 100 parts by weight "Dicrylan" latex 3793 25 now ( _from ciba-Geigy Ltd)

10 ^ ige formic acid 17 ς η η η solution ^χ 11->

Such a mixture resulted in a solid, white, opaque, crack-free, hard cast body with a very high surface gloss.

Example 2

Mixture No. 4 was used as a brush-on coating on chipboard, plaster castings, hardboard, and corrugated boards used and delivered a hard, crack-free, waterproof, shiny surface protection.

Example 3

Mixture No. 4 100 parts by weight of sand 100 "« "

This mixture was used as a (0.5 to 1 mm thick) surface coating Used on plasterboard, polyurethane foam insulation boards, chipboard and foamed UF boards with the achievement of hard, water- and abrasion-resistant surface layers on these substrates.

Example 4

Mixture No. 4 100 parts by weight

Plaster 1 100 "» "

This mixture resulted in similar surface layers on the above substrates, but which were somewhat less resistant to abrasion was.

The same mixture resulted in potted into thick blocks (from 7 to 10 mm thick), hard, sharp-edged, for many applications (e.g. road marking posts with reflective glass bead surfaces) suitable castings.

Example 5

Mixture No. 4 100 parts by weight

Stucco 200 · '» ⁿ (hemihydrate)

This mixture resulted in dimensionally accurate castings of high water resistance and extreme hardness. The surfaces of this Goat bodies were then mixed with Mixture No. 4 (without filler) to form products with a glossy finish and improved surface hardness coated.

Alternatively, the resin / plaster of paris moldings were ground and polished to obtain natural marble-like products.

B09810 / 1D03

Example 6

Mixtures No. 2, 3 and 4 proved to be useful adhesives, for example for gluing in bristles in the metal frames or backs of brushes and for such Applications can be stretched with plaster of paris as described above.

Unfilled mixtures, such as the mixtures No. 2, 3 and 4, can be used for joining wood and others cellulosic materials as well as a number of porous non-cellulosic materials are used when there are wide gaps between the elements to be combined, which must be filled with a crack-free (non-disintegrated) adhesive or when no pressure is applied to the surfaces to bring them into appropriately close contact.

Example 7

(a) For other mixtures that are used for casting purposes and surface coatings (crack-free) include:

"Aerolite 300" 100 parts by weight

"Scott Bader Latex _it -""" 33061 »ι?

10% formic acid 10 "" ⁿ

(transparent in 1 mm layer thickness)

609810/1003

2S3A451

(b) "Aerolite 300" 100 parts by weight

"Scott Bader Latex
33061 » 15th η π Il TiO ₂ 20th π ti π 20% formic acid 10 N It
(White, η
opaque)

(c) 100 UF + 10 to 50 parts "Scott Bader Latex 13/002" with formic acid catalyst

to achieve non-cracked castings and coatings.

Example 8

Mixture No. 4 was mixed with an equal weight of plaster of paris and the combined mixture was used to impregnate two layers of short fiber mats (the weight of the glass mat per square meter was 300 g). The impregnated material was left uncovered for 16 hours at dried about 23 ^° C. Two laminates of this type were then taken together and pressed under a pressure of 50 bar in a hydraulic press and d «j. Heated to 90 ^° C. for 15 minutes. In this way, stiff, smooth-surfaced laminates with 12% by weight of glass fibers were obtained.

Example 9

(a) Equal parts of plaster of paris and mixture No. 4 were used for the impregnation

6G9äio / mn 3

three layers of fiberglass mats made of chopped strands (with a surface density of 300 g / m) are used. The covered with Aliiminiumfolienbahnen uncured laminate was pressed bar in a hydraulic press under a pressure of 25 and heated therein for one minute at 6O ⁰ C. The edges of the mold body were delimited by a square metal gasket shape 3 mm thick. A shaped but still more flexible molded body was removed from the mold and ^{cured overnight at 90 °} C. to obtain a stiff plate. A mechanical test of the same

—2 resulted in a flexural modulus of 5150 MNm and a flexural

-2
strength of 55 MNm. The glass fiber content was 9% by weight.

(b) This procedure was carried out with half the amount of plaster of paris repeated, but with four layers of fiberglass mats. The flexural modulus was determined to be 4,200 MNm and the

_2 '
Flexural strength to 79 MNm.

(c) Other materials were made using both three as well as four layers of fiberglass mats with the following Mixtures made:

Mixture No. 4 100 parts by weight

Fine sand 200 ^M ""

Mixture No. 4 100 " ^{M n}

Kaolin 25 "" ^w

Mixture No. 4 100 " ⁿ "

609810/10 03

Kaolin 50 parts by weight

Fine sand 50 ^M » ^w

Mixture No. 4 100 ⁿ " ⁿ

Bentonite 25 "" "

Fine sand 100 « " ⁿ

In these cases, the materials were molded under low pressure (about 1 bar) without a limiting seal and initially ^{heated to 70 °} C. between aluminum foils for 2 minutes. The foils were then removed and the composites were ^{heated to 90 °} C. for 16 hours for practically complete curing.

(d) In another case, layers of fiberglass mats impregnated with equal amounts of plaster of paris and Mix # 4 were placed between aluminum foils in a 3 mm thick mold frame so that the initial thickness of the charge was 6 mm and only about 1/2 the surface area of the Shape covered. The mixture was placed between the plates of a hydraulic press which was at 60 ^° C. and held tightly against the plates for 0.5 minutes before the press was closed. The molding was carried out for 1 minute using a pressure of 25 bar. A flexible molded body corresponding to the shape of the mold and having a practically uniform glass distribution was obtained. This was then heated ^{to 90 ° C. for 16 hours.} The glass content was 12% by weight.

B 0 9 6 10/1003

Example 10

The following materials - were put into a paddle mixer given:

100 parts by weight mixture No. 4

50 " ^H " kaolin
100 "" »Fine sand

13 "" strands of fiberglass chopped to an inch

These were mixed into a paste for about 10 minutes, the formic acid from Mixture No. 4 being added in the last minute. The paste was removed and pressed for 2 minutes between heated plates (70 ^° C.), followed by cold pressing for 10 minutes at about 5 bar. The molded plate was post-cured for 16 hours at 9O ⁰ C.

Example 11

A pipe was made by impregnating short fiber mats of chopped strands of glass fiber with equal amounts of Mixture No. 4 and plaster of paris. These were helically wrapped around a glass tube previously wrapped with a polyethylene terephthalate film. The wound structure was smoothed and consolidated and the entire arrangement was heated ^{to 90 ° C. in an oven for 15 minutes.} A flexible but self-supporting pipe could then be removed from the glass

6 0 9 8 1 (3/1 G G 3

tube removed, the polyethylene terephthalate film is removed and the tube can be post-cured at 90 ⁰ C for 3 hours. In this way a stiff, impact-resistant pipe was produced «

Example 12

A mixture of equal amounts of mixture No. 4 and plaster of paris was brought into a cylindrical mold which was rotated about its longitudinal axis until the mixture gelled (about 45 minutes at 23 ^° C.). The tube produced was removed and allowed to dry at room temperature for 24 hours. As in the previous example, this was wrapped in a helical manner with impregnated glass fiber mat and then the entire arrangement was ^{heated to 90 °} C. for 3 hours to obtain a stiff, impermeable tube.

Example 13

. The mixture # 4 was poured into a 2 mm thick molded sealing frame between layers of polytetrafluoroethylene-coated glass fabric and heated, the casting held in this arrangement for 3 minutes by accommodating between hot metal plates at 70 ⁰ C. A flexible, opaque material was removed and placed in an oven at 60 ⁰ C. After 2 hours a plate of good transparency was obtained. The cast body was and remained free of cracks.

b 0 9 8 1 0/1 Π Π 3

Example 14

"Aerolite 300" was acidified with 10% by weight of a 10% formic acid solution and the resin was used to impregnate short fiber mats made from chopped glass fibers. The laminate was gelled by heating to 70 ^° C. for 3 minutes between PTFE-coated glass fabric and hot metal plates, as described in the previous example. The laminate was heated overnight at 6O ⁰ C and then overnight at 90 ⁰ C. During the review, the resin was found in the laminate as cracked. A laminate produced in the same way from mixture no. 4, on the other hand, was found to be free of cracks.

Example 15

The following mixtures were produced:

A. 100 parts of "Comparative Resin"

("Aerolite 300" + 10 %

a 1 above formic acid solution)

33 1/3 parts kaolin
133 1/3 parts fine sand

B. 100 parts Mixture No. 4

33 1/3 parts kaolin
133 1/3 parts fine sand

Both A and B were used to impregnate short fiber mats made from chopped glass fibers, which then

f 0 9 8 1 0/1 -0 Π 3

3 minutes were lightly pressed at 7O ⁰ C for between hot plates as described in the preceding examples, to form plates, which were cured at 90 ⁰ C for 15 hours.

Strips of ^ Eder sample were immersed in V / ater of 80 ⁰ C, 60 ° C and AO ⁰ C (120 hours). The samples were then removed, wiped dry and weighed. They were then left to dry overnight at room temperature and then ^{dried overnight at 60 °} C. and finally weighed again. The total change in thickness of each sample was also determined. The results are summarized below:

At 80 ⁰ C

Change in weight after diving

A- 8.1 %
B - 0.75 % ■

Change in weight after dipping and drying

A - 21.7%
B - 15 %

Change in thickness after dipping and drying

A - 8.2 %
B- 3.5%

10/10 Π 3

At 60 ° C

Change in weight after diving

A + 0.4 % B + 3.6 96

Change in weight after dipping and drying

A - 12 % B - 8.8 %

Change in thickness after dipping and drying

A- 4.7 % B- 3.6%

At 4O ⁰ C

Change in weight after diving

A + 4.8 % B + 6.1 %

Change in weight after dipping and drying

A - 4.6 % B- 4.3 %

Change in thickness after dipping and drying

A - 8.1 % B- 2.5 %

B 0 9 8 1 0/1 Π Ό

25344b1

It was also observed that the surfaces of samples of material A loose and powdery products, which was in the submerged in water at 8O ⁰ C samples on ausgeprägtesten. The surfaces of samples of material B produced according to the invention were noticeably more cohesive and, unlike those of material A, they were not prone to material loss from the surface due to slight abrasion. Material B thus showed significantly better resistance to attack by water than sample A.

G 0 9 8 1 Π / 1 Π η 3

Claims (12)

, Claims 1. Liquid adhesive or binder based on resin, characterized by 5 to 95% by weight (preferably 20 to 80 %) of a polymer latex and 95 to 5% by weight (preferably 80 to 20 %) of an aqueous solution of a thermosetting resin. 2. Adhesive or binder according to claim 1, characterized in that that the resin is urea-formaldehyde resin, melamine-formaldehyde resin or a mixture thereof. 3. adhesive or binder according to claim 1 or 2, characterized in that the polymer latex is a synthetic or natural latex or an aqueous emulsion based on acrylic polymer and in particular is formed by a neoprene. 4. Adhesive or binder according to one of the preceding claims, characterized by an additional content of resin curing catalyst in an amount insufficient to precipitate the latex, so that the composition is still liquid and homogeneous _; which is formed in particular by an acid such as formic acid. (i 0 9 8 1 ϋ 1 1 η η 3 5. Adhesive or binder according to one of the preceding claims, characterized by an additional content on an alkali silicate, for example sodium silicate. 6. adhesive or binder according to claim 5, characterized by 5 to 95 wt.% (Preferably 20 to 80%) and silicate 95 to 5% by weight (preferably 80 to 20%) of the combined resin solution and latex. ' 7. Adhesive or binding agent according to one of the preceding Claims in a separate pack, characterized by a plurality of packs, each of which has at least one component of the composition, which are kept separate until use. 8. A method for coating surfaces, characterized in that that a liquid adhesive or binding agent is used according to one of the preceding claims. 9. Method of joining objects with similar ones or dissimilar surfaces or surface materials with one another, characterized in that at least one A liquid adhesive or binding agent according to one of Claims 1 to 7 is applied to the surfaces and then to the surfaces are pressed together. 10. Method of joining objects with similar ones 6 0 9 8 1 G / 1 0 <Q 3 253A451 or dissimilar surfaces or surface materials with one another, characterized in that on a surface at least one component of a liquid adhesive or binding agent according to one of claims 1 to 7 and to the other surface the other component (s) of the composition applied and the surfaces are then pressed together. 11. A method for binding particulate or fiber materials, characterized in that a liquid adhesive or binder according to any one of claims 1 to 7 applied and the material in any desired shape is brought. 12. A process for the production of moldings, characterized in that a liquid adhesive or binder according to any one of claims 1 to 7, with or without particulate or fibrous reinforcing materials, is produced and is cast in a mold. ■ 609.810 / 1003