WO1994002520A1

WO1994002520A1 - Environmentally safe chemical reactions for method of producing new types of environmentally safe materials and products obtained by said methods

Info

Publication number: WO1994002520A1
Application number: PCT/NO1993/000099
Authority: WO
Inventors: Tore Ledaal
Original assignee: Tore Ledaal
Priority date: 1992-07-16
Filing date: 1993-06-25
Publication date: 1994-02-03
Also published as: NO922808D0; NO922808L; AU4515293A

Abstract

Maximum environmentally compatible chemical reactions as a process for preparing environmentally compatible groups of products and special products. Key words: novel and modified polymers, novel varnish and paint binding agents, special coatings, water binding agents, ion binding agents. Certain - viewed in purely theoretical terms - optimum environmentally compatible chemical reactions, viz., additions and water split-off reactions in water having 100 % yield can be realized, approximately, in practice, so that product isolation and purification in many cases may be omitted. Ready-for-use aqueous solutions and important groups of products and special products are obtained, practically free of organic solvents and migrating and/or volatile compounds except for water. Interesting products of greatly varying water resistance, hydrophililicity and degradability in nature are easily available. This applies, inter alia, to greatly modified and partly completely novel polymers, for example, novel binding agents for varnish and paint, special coatings and anti-graffiti and anti-friction coatings and novel, efficient water binding agents and ion binding agents. The work-saving reactions also permit, inter alia, a simple introduction of alkyl groups, for example methyl, into certain plastics and natural substance polymers, and open up for a novel and environmentally compatible industrial utilization of large quantities of methanol.

Description

ENVIRONMENTALLY SAFE CHEMICAL REACTIONS FOR METHOD OF PRODUCING NEW TYPES OF ENVIRONMENTA1-LY SAFE MATERIALS AND PRODUCTS OBTAINED BY SAID METHODS.

I t i s a wel l-known fact that organic solvents cause problems with respect to health and environment . It would therefore be envi ronmental ly and economi cally advantageous if organi c solvents could be replaced by water to a far greater extent than now . Unwanted by-products that are formed in some degree during most chemi cal reactions also create environ¬ mental problems and loss of working time and money .

The most advantageous chemical reactions imaginable (apart from polymerizations) would be additions and water split-off reactions in an aqueous environment having 100$ yield of the desired products, without any net energy consumption.

Among the chemical reactions known so far, there are hardly any which fulfill such extremely stringent requirements. Certain condensation and/or esterification reactions come, closest perhaps, but esterifications, for example, are normally an equilibrium reaction, in which optimum yield depends upon the absence, or removal, of water. In a completely aqueous environment it may therefore seem rather unreasonable to expect optimum results from water split-off reactions. Nevertheless, contrary to what would be expected, this has proved possible. Even greatly diluted aqueous solutions of starting materials which contain suitable atomic groups react approximately quantitatively during water split- off reactions. Since practically no by-products other than water are being formed, time-consuming isolating and washing processes are avoided. The reactions are carried out under continuous stirring and moderate heat application, for example, heating at 60-100°C, and continue under boiling (and possibly foam formation) until the reaction is completed. Atomic groups making water split-off possible may exist within the same molecule or in different molecules.

II

Typical groups are -OH and -C-N-H. These can serve to build

up chains of various lengths and are used both as bridge fastenings and bridges for linking molecules together. The reactions are suitable for, inter alia, a nearly unlimited modification of certain plastics and natural substances. This makes possible the building up and rebuilding of molecular systems with desired properties, such as great variation with respect to water resistance, hydrophilicity and degradability in nature. Polymers may, for example, be equipped with novel side chains of different lengths. These may be provided with branches which again may be branched. The same applies to bridges between polymer molecules. The new modified molecules can be divided into three main types:

1) compounds having side chains without branches or with few branches,

2) compounds having side chains with many branches,

3) compounds in which similar or dissimilar (polymer) molecules are linked by bridges of various lengths.

The bridge molecules may also be regarded as bands of condensed ring systems having a least ring size of from 8 rings and up, and having varied contents of polar groups.

0

II

Also certain inorganic groups such as -Si- can be introdu¬ ced. The bridges and the corresponding rings can be made more or less rigid, inter alia, form networks of gel-forming systems having great stability and water binding property. By varying ring sizes and contents of polar groups, it is also possible to prepare effective metal ion binders. Here are new possibilities for achieving water purification, including desalination of sea water and removal of radioactive cesium and strontium, etc. from drinking water. In the areas of paints, varnishes and surface coatings of various kinds, new possibilities are opening up. The shortcomings of the hitherto available varnishes, paints and opaque stains are only too convincingly demonstrated in practice. Moisture and water get too easily into and through the coatings, but escape again only with difficulty, and far too slowly. Thus, the usual damages occur: fungus and rot in woodwork, flaking of paint chips and frost damage to masonry and concrete. By means of a correctly adjusted balance between hydrophilicity and water resistance in the binders such problems are avoided. In a surface coating having even moisturerizing and swelling, this will lead to a limited water penetration and water transfer, and when the exposure to moisture and water ends, the coating dries rapidly and evenly without blistering, cracking or chipping.

Usual varnish and paint auxiliaries such as thickeners, plaεticizers, surfactants, etc., can be very simply prepared by means of said reactions, and can also be anchored to the main binder. Thus, the coating can consist of a single polymer system, without migrating and volatile components and having water as the only solvent. It seems possible to produce coatings having desired properties for nearly any purpose whatsoever, including the protection and conserva- tion of different types of surfaces. Through subsequent heat treatment it will in certain cases be possible to form chemical bonds between the coating and the surface.

Many of the coatings will presumably be particularly suitable for use under water, both on permanent and mobile structu¬ res. Corresponding to the manner in which the exterior water layer of kelp and sea tangle protects these against damages from storm and wear, the coatings will be protected by an exterior water layer which continually is being replaced. By means of this, fouling will effectively be prevented, so that there can be obtained novel anti-fouling coatings completely free of toxicity and solvents for ships, etc. Far more importantly, such coatings are capable of providing sliding surfaces against the water, the friction being reduced to a fraction of what is normal. Thus, increased velocities and/or lower energy consumption can be obtained. This opens up for the development of novel types of anti¬ friction agents or sliding agents for skiing or aqueous sport activities, boating and ship transport. With respect to the last of these, significant savings of energy and fuel can be obtained, resulting in reduced emissions of environmentally hazardous substances, such as CO2, N0_χ and NO2.

What has been mentioned in the preceding description can form the basis for a very large number of patents directed to processes for the preparation of specific products.

In this application the main emphasis is placed on patent claims directed to general methods and/or principles associa¬ ted with important environmentally related groups of substan¬ ces based on the main principle of maximum environmentally compatible chemical reactions, as will be apparent from descriptions, examples and patent claims.

Stoichio etrical amounts of more or less water soluble starting materials in monomer, oligomer or polymer form containing groups which make possible a joining of them by addition or water split-off, as, for example, polyvinyl alcohol, polyacrylic acid, polyacrylic amide, or a natural substance of, for example, carbohydrate type, are reacted in water by addition in a desired sequence. The reaction takes place under continuous stirring and at an initial heat application of 60-100°C and continues under boiling and possible foam formation until a completely reacted, ready-to- use, solution is obtained. General Normal Procedure

Selected stoichiometrical amounts of substances as mentioned above are reacted in water in a chosen sequence so as to obtain, with the greatest probability, the desired molecular structures. The substances are used in ratios which can vary from under 1% to over 50$ of the total weight of the solution. The reactions occur under continuous stirring, and at an initial heat application of 60-100°C and stirring at

10 about 1000 rpm. Under normal conditions, after a noticeable heat change has started, the heat coupling is maintained at about 100°C and the stirring at 1000 rpm for 15-30 minutes. Then the heat is turned off and the stirring is reduced to 500 rpm for about 20 minutes. The mixture is weighed, and ¹? the contents of the product are calculated while taking into account the assumed maximum number of possible water split- off reactions per mole. By the addition of water or water evaporation the ready-to-use solution is adjusted to a desired concentration.

20

Example 1

A clear water-based varnish having anti-graffiti and sliding characteristics.

2 Preparation procedure:

4.4 parts by weight of polyvinyl alcohol having a mean molecular weight of 72 000 (Fluka Chemika 81384) are reacted with 4.5 parts by weight of formamide 99 (Merck) in 34 parts by weight of water. The water is added little by little

?° while stirring into a lump-free paste. The mixture is processed according to normal procedure. Thereafter, 9.60 parts by weight of methanol are added, and normal procedure is repeated.

35 The result: a clear, ready-to-use varnish which is nearly colourless and approximately odorless. Example 2

An anti-graffiti agent for special coating on painted and unpainted surfaces of wood, masonry, concrete, etc.

5 Preparation procedure:

6.00 parts by weight of potato starch (in the form of ordinary potato flour) and 6.60 parts by weight of α-D glucose monohydrate are reacted in 100 parts by weight of water according to normal procedure. Thereafter, 12 parts by

¹⁰ weight of methanol are added, and the normal procedure is repeated.

Example 3

An anti-friction coating, a sliding agent, for sliding !5 surfaces against water and water-moisturized media.

Preparation procedure:

6.60 parts by weight of potato flour, 15.00 parts by weight of formamide, 22.00 parts by weight of methanol and 100 parts

20 by weight of water are reacted according to normal procedure.

Example 4

An anti-friction agent, a sliding agent for sliding surfaces against water and water-moisturized media, characterized in 25 that ordinary starch molecules have been increased by 10 mole for formamide and 20 mole for methyl groups into a novel complex molecule containing, inter alia, -OCH3 and -NCH3 groups, and that the preparation occurs according to the processes described in the claims.

30

Example 5

A new type of water-binding agent for improved utilization of water, enhanced oil extraction and improvaed control of polluting liquid discharge.

35 Preparation procedure:

0

1.20 parts by weight of carbamide, HgN-C-NHg, are reacted according to normal procedure with 1.13 parts by weight of a 35$ aqueous solution of sodium silicate in 100 parts by weight of water. The product is reacted with 0.72 silicate in 100 parts by weight of water. The product is reacted with 0.72 parts by weight of polyacrylic acid having a mean molecular weight of about 500 000. After a few minutes of heating and stirring the solution is set to a firm gel, which after cooling can bind an additional 100 parts by weight of water which is stirred into it. (Drops of gel having 99$ water content placed on a hot plate at about 200°C will retain their water for several minutes.)

Example 6

A new type of ion-binding agent for water purification, etc.

Preparation procedure:

6.00 parts by weight of carbamide is first reacted with 2.26 parts by weight of a 35$ aqueous solution of sodium silicate in 100 parts by weight of water according to normal pro¬ cedure.thereafter, new 2.26 parts by weight of a 35$ water solution of sodium silicate are added, and the mixture is again reacted according to normal procedure.

Claims

Patent Claims

1.

A maximum environmentally compatible, efficient and inex¬ pensive process for the production of novel, important product groups, inter alia, modifications of plastics and natural substances, based on an unexpectedly effective water split-off reaction in a aqueous environment without the use of organic solvents, catalysts or other auxiliary substances, c h a r a c t e r i z e d i n that the main product is formed with an approximately 100$ yield and with water as the only solvent and by-product, and in that time-consuming and costly isolation and purification processes can be omitted, the reaction solutions being immediately ready-for-use products, possibly after an adjustment of the concentration and addition of anti-oxidants, etc.

2.

Polymers having new unbranched side chains, c h a r a c t e r i z e d i n that a more or less water soluble polymer is joined, in an aqueous environment, to a glycol, H0-(CH₂)_n-0H or an alcohol ROH is R = CH₃, -C₂H₅, C₃H7. . _L or with combinations of glycols and alcohols according to the process of claim 1.

3.

Polymers having novel, branched side chains, c h a r a c t e r i z e d i n that a more or less water soluble polymer is joined, in an aqueous environment, to aldehydes RCHO, ketones R₂C0, amides RC0NH₂, glycols H0- (CH2)_n-0H, alcohols ROH and/or to combinations of such compounds according to the process of claim 1.

4.

Bridge polymers which may be conceived of as a network of condensed rings having a least possible ring size of 8-10-12, etc. , c h a r a c t e r i z e d i n that 2 equivalents of a more or less water soluble polymer, or one equivalent of each of two different polymers, are joined in an aqueous environment by bridges of desired length and composition, unbranched or branched, built up as disclosed in claims 2 and 3 respec¬ tively, according to the process of claim 1.

5.

Environmentally compatible varnishes and paint binding agents having water as their only volatile component, c h a r a c t e r i z e d i n that optimum balance between hydrophilicity and water resistance is obtained by building selected atomic groups into the molecules of the binding agent, and that these are prepared according to the process of claims 1-4.

6.

Environmentally compatible coating agents for protecting the surface coatings, "finish," of the most varied types of material, such as plastics, leather, metals, porcelain, etc., c h a r a c t e r i z e d i n that the coating agents are prepared according to the process of claims 1-4.

7. Environmentally compatible anti-graffiti agents for protec¬ ting the most varied types of surfaces against dirt and graffiti , c h a r a c t e r i z e d i n that the agents are prepared according to the process of claims 1-4.

8.

Environmentally compatible anti-friction agents, sliding agents and new types of non-toxic anti-fouling coatings for ships and leisure crafts and aqueous sports and skiing, etc. c h a r a c t e r i z e d i n that they are highly hydrophilic at the same time as they are water resistant, and that they are prepared according to the process of claims 1-4.

9. Water-binding agents and highly efficient surface-active additives for water-based solutions, emulsions, etc., for improved utilization of water, increased degree of oil extraction and control of liquid discharge, etc., c h a r a c t e r i z e d i n that they are prepared according to the process of claims 1-4.

10.

Metal ion binders, desalination agents and water purification agents, c h a r a c t e r i z e d i n that they contain a network, of varying mesh sizes, of artificial or natural polymers or combinations of such, and that they are prepared according to the process of claims 1-4.

AMENDED CLAIMS

[received by the International Bureau on 15 December 1993 (15.12.93); original claims 1-10 replaced by amended claims 1-5 (2 pages)]

1.

A process for the preparation of a coating agent for use under water or on surfaces exposed to moisture, c h a r a c t e r i z e d i n that compounds having readily reactive OH groups, such as polyvinyl alcohol or starch, are reacted with compounds having reactive H-atoms under water split-off reactions.

2.

Varnish having anti-graffiti and sliding properties, c h a r a c t e r i z e d i n that (4-5) parts by weight of polyvinyl alcohol having a mean molecular weight 72,000 are reacted with (4-5) parts by weight of formamide 99* in (30-40) parts by weight of water which is added little by little, while being stirred and heated to 60°C-100°C, and (9-10) parts by weight of methanol are thereafter added, with continued stirring and heating.

3.

Anti-graffiti agent for special coating on painted and unpalnted surfaces, c h a r a c t e r i z e d i n that (6-7) parts by weight of potato starch and (6-7) parts by weight of L-D glucose monohydrate are reacted in 100, 0 parts by weight of water, with stirring and heating, and 12 parts by weight of methanol are thereafter added, with continued stirring and heating.

4.

Anti-friction coating for sliding surfaces against water and water-moisturized media, c h a r a c t e r i z e d i n that (6-7) parts by weight of potato flour, 15 parts by weight of formamide, 22 parts by weight of methanol and 100 parts by weight of water are reacted while being stirred and heated. 5.

Anti-friction agent for sliding surfaces against water and water-moisturized media, c h a r a c t e r i z e d i n that ordinary starch molecules are increased by 10 mole for formamide and 20 mole for methyl groups into a novel complex molecule containing -OH3 and -NCH3 groups and are reacted as described in claim 2.