KR20010012711A - Polyurethane foams - Google Patents

Abstract

The present invention provides hydrogenated polydiene diols having a number average molecular weight of 1,000 to 20,000; Aromatic polyisocyanates; A polyurethane foam composition derived from a reaction mixture comprising a plasticizer and a blowing agent. Preferably, the polyurethane composition further comprises an adhesive resin. The invention also relates to a process for producing polyurethane foams and to articles containing polyurethane foams.

Description

Polyurethane Foam {POLYURETHANE FOAMS}

Polyurethane foams with high elasticity are typically produced from polyether triols and isocyanates. Polyether triols typically have a number average molecular weight of 4,500 to 6,000 and an average functionality of hydroxyl groups of 2.4 to 2.7 per molecule. Toluene diisocyanate, diphenyl methane diisocyanate, toluene diisocyanate / diphenyl methane diisocyanate mixture, and modified toluene diisocyanate or diphenyl methane diisocyanate versions are used to produce foams with a wide range of processing tolerances. Isocyanate functionality is typically 2.0 isocyanate groups per molecule, in most cases 2.3 or less. Polyether triols form elastic foams when combined with isocyanates having 2.0 to 2.3 isocyanate groups per molecule under conditions that promote foaming.

US Pat. No. 4,939,184 describes the production of polyethane foams from polyisobutylene triols and diols prepared from cations. Polyisobutylene is premixed with isocyanates, ie isocyanates which are a mixture of meta- and para-isomers of toluene diisocyanate with a functionality of 2.0. Water is then added as foam to form the polyurethane foam. The foams obtained have low elasticity and are useful for energy absorption applications.

International (PCT) application WO 97/00902 describes highly elastic polyurethane foams produced from polydiene diols. The elasticity of the foam is achieved by adding aromatic * polyisocyanates having the functionality of 2.5 to 3.0 isocyanate groups per molecule to ensure sufficient crosslinking. The resulting polydiene diol foams exhibit superior wet aging properties compared to conventional polyurethane foams.

U. S. Patent No. 5,710, 192 describes high elastic, high tear resistant polyurethane foams produced from polydiene diols. The heat resistance of the foam is achieved by selecting an appropriate amount of aromatic polyester with the functionality of 1.8 to 2.5 isocyanate groups per molecule to ensure sufficient crosslinking. The resulting polydiene diol foams show good tear resistance and are close to white in color.

In the foams described above, difficulties are encountered in processability and control of cell size and cell distribution. It is desirable to have very workable foams having small uniform cell size and distribution while retaining sufficient elastic foam properties.

The present invention relates to polyurethane foams, in particular flexible polyurethane foams containing polyols and aromatic isocyanates. The invention also relates to a process for the production of polyurethane foams and to articles containing the polyurethane foams.

1 shows the influence on the viscosity of the oil.

2 shows the effect on the foam density of the oil.

3 shows the effect of water content on the density of foams, such as the foams of the present invention.

According to a preferred embodiment, the invention preferably comprises 100 parts by weight (pbw) of polydiene diols having a number average molecular weight of 10,000 to 20,000, more preferably 1,000 to 10,000, most preferably 3,000 to 6,000, aromatic polyisocyanate 20 Elastic polyurethane foam comprising from 55 pbw up to 200 pbw plasticizer, more preferably hydrocarbon processing oil, and blowing agent.

In a preferred embodiment, the hydrogenated polydiene diols have hydroxyl groups of 1.6 to 2, more preferably 1.8 to 2, per molecule, and the polyisocyanates used have a compatibility of 2.5 to 3.0 isocyanate groups per molecule. The isocyanate is preferably added at a concentration close to the equivalent number of isocyanate groups and hydroxyl groups. Preferably, the NCO: OH molar ratio is in the range of 0.9 to 1.2.

Polydiene diols used in the present invention are typically anionic. Anionic polymerization is well known to those skilled in the art and is described in US Pat. Nos. 5,376,745, 5,391,663, 5,393,843, 5,405,911 and 5,415,168.

The polymerization of the polydiene diols begins with a monolithium initiator containing a dilithium initiator which polymerizes the conjugated diene monomer at the protected hydroxyl group or at each lithium site. Due to cost advantages, conjugated dienes are typically 1,3-butadiene or isoprene, although other conjugated dienes will also work well in the present invention. When the conjugated diene is 1,3-butadiene and the resulting polymer is hydrogenated, anionic polymerization typically requires structural modifiers such as diethyl ether or 1,2- to obtain the desired amount of 1,4-adduct. It is controlled by diethoxyethane.

Anionic polymerization is terminated by the addition of a functionalizing agent. The functionalizing agents used are known to those skilled in the art and are described in US Pat. Nos. 5,391,637, 5,393,843 and 5,418,296. Preferred functionalizing agent is ethylene oxide.

The polydiene diol is preferably hydrogenated to improve stability so that at least 90%, preferably at least 95%, of carbon to carbon double bonds in the diol are saturated. Hydrogenation of these polymers and copolymers is well established, including hydrogenation in the presence of catalysts such as RANEY ^R nickel, precious metals such as platinum, soluble transition metal catalysts and titanium catalysts, as described in US Pat. No. 5,039,755. It can be achieved by the method.

Hydrogenated polydiene diols provide a stable elastic foam. The polydiene diols preferably have 1.6 to 2, more preferably 1.8 to 2 terminated hydroxyl groups per molecule. For example, an average functionality of 1.8 means that about 80% of the molecules are diols and about 20% of the molecules are monools. Since most product molecules have two hydroxyl groups, the product is considered to be a diol. The polydiene diols of the present invention have a number average molecular weight of 1,000 to 20,000, more preferably 1,000 to 10,000, most preferably 3,000 to 6,000. Preference is given to hydrogenated polybutadiene diols, in particular those having from 40% to 60% of 1,2-adducts.

Diene microstructures are typically measured by ¹³ C nuclear magnetic resonance (NMR) in chloroform. If after the hydrogenation the polymer has up to 40% 1,2-butadiene adduct, it is preferred that the polybutadiene diol has at least 40% 1,2-butadiene adduct since the polymer after hydrogenation will be a waxy solid at room temperature. . Isoprene polymers typically have at least 80% 1,4-isoprene adducts to reduce the glass transition temperature (T _g ) and viscosity.

The polydiene diols used in the present invention typically have a hydroxyl equivalent weight of about 500 to about 10,000, more preferably 500 to 5,000, most preferably 1,500 to 3,000. Thus, for polydiene diols, a suitable number average molecular weight will be between 1,000 and 20,000, more preferably between 1,000 and 10,000, most preferably between 3,000 and 6,000.

The hydrogenated polydiene diols of the examples have a number average molecular weight of 3300, a functionality of 1.92 and a 1,2-butadiene content of 54%. The polymer is hydrogenated to remove at least 99% of carbon to carbon double bonds. Such polymers are hereafter referred to as diol 1 herein.

The polydiene monools used are prepared substantially as described herein except that the polymerization is initiated with a monolithium initiator. Monohydroxylated polydiene polymers typically have a number average molecular weight of 500 to 20,000, preferably 2,000 to 8,000. The hydrogenated polydiene monools of the examples have a number average molecular weight of 3850, functionality of 0.98 and 1,2-butadiene content of 48%. The polymer is hydrogenated to remove at least 99% of carbon to carbon double bonds. Such polymers are hereafter referred to as monool 1 herein.

The number average molecular weight referred to herein is the number average molecular weight measured by gel permeation chromatography (GPC) calibrated with a polybutadiene standard with a known number average molecular weight. The solvent for GPC analysis is tetrahydrofuran.

The isocyanates used in the present invention are aromatic polyisocyanates because they have the desired rapid reactivity to produce the foams. Since saturated polydiene diols have about 2 hydroxyl groups per molecule, polyisocyanates having a functionality of 1.8 to 3.0, preferably 2.5 to 3.0, are typically crosslinked to produce stable, high load-resistant, high-elastic foams. Used to achieve bond density. The use of lower functional isocyanates results in less stable foams with lower load resistance and reduced elasticity. Higher isocyanate functionality will produce foams with too high closed cell content that will negatively affect physical properties.

An example of a suitable aromatic polyisocyanate is MONDUR ^R MR (Bayer), which is a polymer diphenyl methane polyisocyanate, typically having an isocyanate functionality of 2.7. Also used is RUBINATE ^R 9225 (ICI Americas), a liquid isocyanate consisting of a mixture of 2,4-diphenyl methane diisocyanate and functional 2.06 4,4-diphenyl methane diisocyanate; The addition of oils or monools to foams made with these lower functional polyisocyanates can lead to foam collapse and requires formulation control.

Oils useful in the present invention are petroleum based process oils. Compositions of such oils may range from paraffinic to naphthenic to highly aromatic. Oils are available including a broad viscosity range of 10 to 1000 centipoise at 100 ° F. (38 ° C.). Preferably, the oil used in the foam of the present invention is a paraffinic, naphthenic or paraffinic / naphthenic oil having a viscosity within the above range. An example of a suitable oil for use in the present invention is SHELLFLEX ^R 371 (Shell Oil Company), a paraffinic / naphthenic process oil having a viscosity range from 100 ° F. (38 ° C.) to 80-100 centipoise.

Since polydiene diols are hydrocarbons, they have good compatibility with hydrocarbon process oils. Also, there is no tendency for oil to be released out of the foam. The addition of oil to the formulation reduces the viscosity, thereby improving processability. 1 shows how the viscosity of a polydiene diol (diol 1) blended with an oil (SHELLFLEX 371; SHELLFLEX is a trademark) depends on the amount of oil in the blend. The addition of up to 200 parts by weight (phr) of oil per 200 million parts of polydiene diol resin will lower the viscosity by a factor of 10 at some of the corresponding temperatures. This reduction in viscosity makes the foams of the present invention easier to manufacture than previous foams and results in more uniform and smaller cell sizes.

FIG. 2 shows the effect of oil (SHELLFLEX 371) concentration on foam density of polyisocyanate (MONDUR ^R MR) and polydiene diol (diol 1) blended with water. Increasing the oil content from 0 to 200 phr increases the density about three times. More compact foams have smaller cells and a very uniform cell size distribution.

Essential components of the polyurethane foams of the present invention are polydiene diols, aromatic polyisocyanates, blowing agents such as water, and plasticizers, preferably oils and / or polydiene monools. Optionally, and preferably the polyurethane foam further comprises an adhesive resin.

Adhesive resins useful in the present invention are relatively low molecular weight predominantly hydrocarbon polymers which are characterized primarily by the ring and ball softening points measured by ASTM standard method E28. Usually, the resin will have a softening point in the range of about 80 ° C to about 120 ° C. However, in certain cases lower softening point resins or liquid resins may be advantageous, for example, to obtain the best adhesion at low temperatures.

Typical adhesive resins are cationic polymerization of a mixture containing 60% piperylene, 10% isoprene, 5% cyclopentadiene, 15% 2-methyl-2-butene and about 10% dimer as described in US Pat. No. 3,577,398. It is manufactured by. This type of resin is marketed as WINGTACK ^R 95 (Goodyear Tire & Robber Company) and has a 95 ° C softening point. The resin may also contain some aromatic character introduced by including styrene or α-methylstyrene in the mixture during the polymerization of the resin.

Other types of adhesion promoting resins useful in the present invention include hydrogenated rosin, esters of rosin, polyterpenes, terpene phenol resins, and polymerized mixed olefins. In order to achieve good thermal oxidation and color stability, saturated resins such as hydrogenated dicyclopentadiene resins such as ESCOREZ ^R 5000 series (Exxon Chemical Company), or hydrogenated polystyrenes such as REGALEZ ^R series (Hercules, Inc.) Preference is given to using resins.

When using a tacky resin with a high softening point, the resin can increase the viscosity of the reaction mixture to the point where foaming does not actually occur. The processability of the foam can be improved by the addition of oil to reduce the viscosity during foaming. Typical oils useful in the present invention include such paraffinic / naphthenic rubber process oils. Suitable oils for use in the present invention are SHELLFLEX 371. The compatibility of these oils with polydiene diol / adhesive mixtures is good. Therefore, there is no tendency for oil to be released out of the foam, and the concentration of oil is adjusted to produce the desired viscosity, foam density, and tack.

The processability of the foam can also be controlled by replacing part of the polydiene diol with polydiene monool. The viscoelasticity of the foam can be adjusted for specific applications by controlling the ratio of diol to monool. Adhesive foams containing a monool content of up to 75% by weight of the diol / monool mixture have been found to be suitable.

The hydrogenated polydiene diol / plasticizer weight ratio is typically at most 5: 1, preferably at most 4: 1, more preferably at most 3: 1, in particular at most 2: 1. The ratio is typically at least 1: 4, preferably at least 1: 3, more preferably at least 1: 1.5, in particular at least 1: 1.

The hydrogenated polydiene diol / adhesive resin weight ratio is typically at most 5: 1, preferably at most 4: 1, more preferably at most 3: 1, in particular 2: 1. The ratio is typically at least 1: 4, preferably at least 1: 3, more preferably at least 1: 1.5, in particular at least 1: 1.

Typically, catalysts and surfactants are needed for foam production.

Surfactants are often added to improve the miscibility of the components and in turn to promote the hydroxyl / isocyanate reaction. In addition, the surface tension of the mixture, which affects cell nucleation and stabilizes the expanded foam, is reduced, resulting in fine cell structure. Preferably the surfactant is a silicone oil. An example of a suitable commercial silicone oil is TEGOSTAB-B8404 (TEGOSTAB is a trademark). Preferred silicone surfactants are DABCO ^R DC-5160. The surfactant, when present, is usually added in an amount of 0.01 to 5 parts by weight (0.01-5 phr), preferably 0.01 to 1 phr per 100 pbw of polydiene diol.

In principle, a catalyst known to catalyze one or more foaming reactions in the system can be used. Examples of suitable catalysts are described in EP 0 358 282 and include amines such as tertiary amines, salts of carboxylic acids and organometallic catalysts.

Examples of suitable tertiary amines are triethylene diamine, N-methylmorpholine, N-ethylmorpholine, diethyl-ethanol-amine, N-cocomorpholine, 1-methyl-4-dimethyl-amino-ethylpiperazine, 3 -Methoxypropyldimethylamine, N, N, N'-tri-methylisopropyl propylenediamine, 3-diethylamino propyl-diethylamine, dimethylbenzylamine and dimethylcyclohexylamine. An example of a carboxylic acid salt useful as a catalyst is sodium acetate. Examples of commercial amine catalysts are DABCO ^R 33-LV and delayed action amine catalyst DABCO DC-1 from Air Products and Chemicals. Suitable organometallic catalysts include tin octoate, tin oleate, tin acetate, tin laurate, lead octoate, lead naphthenate, nickel naphthenate, cobalt naphthenate and dibutyltin dichloride. Further examples of organometallic compounds useful as catalysts in polyurethane production are described in US Pat. No. 2,846,408.

The amount in which the catalyst, or mixture of catalysts, is usually used is in the range of 0.01 to 5.0 pbw, preferably 0.2 to 2.0 pbw per 100 parts of polydiene diol.

Various blowing agents can be used. Suitable blowing agents include halogenated hydrocarbons, aliphatic alkanes and cycloaliphatic alkanes, and water, which are often referred to as chemical blowing agents. Due to the ozone depletion effect of fully chlorinated, fluorinated alkane (CFC), the use of this type of blowing agent is not preferred although they are possible within the scope of the present invention. Halogenated alkanes (so-called HCFCs) in which at least one hydrogen atom is not substituted by halogen atoms have a lower ozone depletion potential and are therefore preferred halogenated hydrocarbons that can be used in physically blown foams. Very suitable HCFC type blowing agents are 1-chloro-1,1-difluoroethane. Hydrofluorohydrocarbons which are believed to have zero ozone depletion potential are even more preferred as blowing agents.

The use of water as a (chemical) blowing agent is also known. Water reacts with isocyanate groups according to the well known NCO / H ₂ O reaction, thereby releasing carbon dioxide which causes blowing to occur.

Aliphatic and cycloaliphatic alkanes are finally developed as another blowing agent for CFCs. Examples of such alkanes are n-pentane, isopentane, and n-hexane (aliphatic) and cyclopentane and cyclohexane (alicyclic).

It will be appreciated that the above blowing agents may be used alone or in a mixture of two or more. Among the blowing agents mentioned, water and cyclopentane have been found to be particularly suitable as blowing agents for the purposes of the present invention. The amount of blowing agent used is usually in the amount applied, ie in the range of 0.1 to 5 pbw per 100 parts of polydiene diol for water and in the range of 0.1 to 20 pbw per 100 parts of polydiene diol for halogenated hydrocarbons, aliphatic alkanes and alicyclic alkanes. to be. Preferably, the blowing agent is water.

Water is preferably added in an amount of 0.5 to 3.5 parts by weight (pbw) per 100 parts of polydiene diol. Preferably, distilled or de-inorganic water is used since impurities can affect the foam reaction.

If desired, flame retardants, fillers and other additives may be added. The selection of suitable additional compounds to be added to the composition to be foamed corresponds to the skill of one of ordinary skill in the art.

Antioxidants and ultraviolet stabilizers can be added to further increase the thermal and light stability of the foam. Interfering phenolic antioxidants such as IRGNOX ^R 1076 (Ciba Geigy) are well suited for the stabilization of these foams. The combination of an ultraviolet absorber such as TINUVIN ^R 328 (Ciba Geigy) and an interfering amine light stabilizer such as TINUVIN ^R 123 (Ciba Geigy) is preferably used for the best resistance to degradation by sunlight.

Polyurethane foams are preferably prepared by blending all components except polyisocyanate. Polydiene diols and, if present, polydiene monools are preheated (typically about 80 ° C.) to reduce viscosity prior to blending. The adhesive resin is also preferably preheated to typically about 150 ° C. After blending, the aromatic polyisocyanate is quickly added and briefly stirred before pouring the mixture into the mold to maintain the expanded foam.

Thus, further aspects of the invention

(i) mixing hydrogenated polydiene diols having a number average molecular weight of 1,0000 to 20,000 with a plasticizer, a blowing agent and optionally a tackifying resin, a surfactant and a catalyst to obtain a mixture;

(ii) combining the aromatic polyisocyanate with the mixture to obtain a blend;

(iii) foaming the blend to obtain a polyurethane foam composition.

Polyurethane foams may be subjected to curing treatment by heating the foams to elevated temperatures, usually from 100 to 160 ° C. for a specific period of time, typically in the range of 10 minutes to 96 hours, preferably 30 minutes to 48 hours. However, the heat usually produced by the exothermic polyurethane foaming reaction is sufficient to ensure complete curing and the process is performed adiabaticly.

Preferred embodiments of the present invention comprise 100 parts by weight of hydrogenated polydiene diols having a number average molecular weight of 3,000 to 6,000 and functionality of hydroxyl groups of 1.8 to 2.0, 0.5 to 3.5 parts by weight of water, and 2.5 to 3.0 isocyanates per molecule. The aromatic polyisocyanate having the functionality of the group is 20 to 200 parts by weight of oil, 0.4 to 0.8 parts by weight of amine catalyst, 0.3 to 0.6 parts by weight of delayed action amine catalyst at a concentration close to the equivalent number of isocyanate groups and hydroxyl groups and Elastic polyurethane foam comprising 0 to 0.06 parts by weight of silicone surfactant. The foams exhibit a superior cell size and cell size distribution over foams made without oil.

A further preferred embodiment of the present invention is 100 parts by weight of hydrogenated polydiene diol having a number average molecular weight of 3,000 to 6,000 and hydroxyl groups of 1.8 to 2.0 per molecule, 0.5 to 3.5 parts by weight of water, isocyanate groups of 2.5 to 3.0 per molecule Aromatic polyisocyanate having a functionality of 50 to 150 parts by weight, 10 to 100 parts by weight of oil, 0.4 to 0.8 parts by weight of amine catalyst, delayed action amine at a concentration close to the equivalent number of isocyanate groups and hydroxyl groups Elastic polyurethane foam comprising 0.3 to 0.6 parts by weight of catalyst and 0 to 0.06 parts by weight of silicone surfactant.

Another preferred embodiment of the present invention is 100 parts by weight of hydrogenated polydiene diol having a number average molecular weight of 3,000 to 6,000 and hydroxyl groups of 1.8 to 2.0 per molecule, polydiene monool having a number average molecular weight of 2,000 to 4,000 75 to 0 50 to 150 parts by weight of an aromatic polyisocyanate having a functionality of an isocyanate group of 0.5 to 3.5 parts by weight of water, and an isocyanate group of 2.5 to 3.0 per molecule, at a concentration close to the equivalent number of isocyanate groups and hydroxyl groups, Elastic polyurethane foam comprising 10 to 100 parts by weight of oil, 0.4 to 0.8 part by weight of amine catalyst, 0.3 to 0.6 part by weight of delayed action amine catalyst and 0 to 0.06 part by weight of silicone surfactant.

In a further aspect, the present invention relates to an article containing the polyurethane foam according to the invention.

The following examples may support individual claims in which each embodiment is claimed to be a patentable invention, but is not intended to limit the invention to the particular aspects.

Surprisingly, it has been found that the addition of plasticizers, for example up to 50% by weight of oil, from polydiene diols to the resulting polyurethane foams results in highly processable foams. Therefore, the present invention relates to hydrogenated polydiene diols having a number average molecular weight of 1,000 to 20,000;

Aromatic polyisocyanates;

Plasticizers; And

A polyurethane foam composition derived from a reaction mixture comprising a blowing agent.

Foams have lower viscosity and more uniform cells during manufacture compared to foams made without oil.

According to a further preferred embodiment, the present invention

Hydrogenated polydiene diols having a number average molecular weight of 1,000 to 20,000;

Aromatic polyisocyanates;

Adhesive resin;

Plasticizers; And

A polyurethane foam derived from a reaction mixture comprising a blowing agent.

The plasticizer is preferably compatible with the hydrogenated polydiene diols. Plasticizers are compatible with hydrogenated polydiene diols when the components do not separate into two layers at room temperature within 12 hours upon subsequent mixing in the desired weight ratio.

The plasticizer may typically be selected from those known to those skilled in the art. Preferably, the plasticizer is an oil and / or hydrogenated polydiene monool having a number average molecular weight of 500 to 20,000.

Example 1

Eight foams are blended as illustrated in Table 1 using polymers, isocyanates (MONDUR ^R MR), catalysts (DABCO ^R 33-LV and DABCO ^R DC-1), surfactants (DABCO ^R DC-5160) and water To prepare. Samples 2 to 7 containing a hydrocarbon process oil (SHELLFLEX ^R 371) are samples representing the present invention. Sample 1 is a comparative example containing no oil. Sample 8 is a comparative example that contains oil but does not use conventional polyether polyols.

In a typical preparation, the polymer and oil are preheated to 80 ° C. Weigh all components of the formulation except isocyanate and place into dry cans and mix using a CAFRAMO ^R stirrer equipped with a 2-inch (5.1 cm) regular pitch propeller. Isocyanate is then added and mixing continued for about 45 seconds. By this time the material begins to foam and is poured into the paper bucket. After the foam has stabilized and skins formed, the foam is post-baked at 110 ° C. for 10 minutes in an oven. Specimens are cut from bun to measure foam density, hardness at 40% compression, elasticity and hysteresis.

density

The density is measured from the weight of the block and its volume. The results are shown in Table 2.

Shout

A 16 mm diameter (16.3 g) steel ball is dropped onto a block of foam measured 10 x 10 x 5 cm from a 51.6 cm height through a 38 mm inner diameter transparent plastic tube. The recoil height is measured and the elasticity is calculated as 100 x (rebound height / drop height). The results are shown in Table 2.

Compression Hardness and Hysteresis Loss

Compression hardness and hysteresis loss are measured on an INSTRON ^R machine model 5565. A block measuring 10 x 10 x 5 cm is placed between two parallel plates, 60% compressed and unloaded at a crosshead speed of 12.5 cm / min for 4 cycles. In the fourth cycle, the force required to compress the foam 40% is recorded and the compressive hardness of the foam is measured. The hysteresis loss is calculated as the area under stress / curve height of the fourth cycle relative to the first cycle. The results are shown in Table 2.

Foam Formulation Sample Dior ¹ (phr) Oil (phr) Water (phr) Isocyanate (phr) Amine catalyst (phr) Delayed action amine catalyst (phr) Surfactant (phr) One 100 0 One 23.5 0.4 0.3 0.02 2 100 11.1 One 23.5 0.4 0.3 0.02 3 100 33.3 One 23.5 0.4 0.3 0.02 4 100 100 One 23.5 0.4 0.3 0.02 5 100 200 One 22.1 0.4 0.3 0.02 6 100 200 2 37.0 0.4 0.3 0.02 7 100 200 3 51.8 0.8 0.6 0.04 8 100 100 One 23.5 0.4 0.3 0.02 ^One sample 1 to 7 uses hydrogenated polydiene diol (Mn = 3300, f = 1.92); Sample 8 uses 4800 molecular weight polyether triol (ARCOL ^R 11-34).

Foam properties Sample Density (g / l) Hardness at 40% compression (N) Resistance (%) History loss (%) Cell size distribution Foam cell structure One 109 27.8 50 14 Wide range Very fine 2 124 31.0 54 13 Wide range Very fine 3 135 23.5 56 16 Narrow Very fine 4 202 20.8 50 13 Very narrow Very fine 5 339 --- 32 --- Very narrow Very fine 6 267 --- 50 --- Very narrow minuteness 7 163 9.6 36 8 Very narrow minuteness 8 ^a --- --- 15 --- --- middle ^a foam is very oily and shows poor strength.

Samples 1-5 are similar formulations with increased oil content from sample 1 (oil-free) to sample 5 (200 phr oil). Samples 1 to 5 all contained 1 phr of water and thus all of them foamed to about the same volume and each expanded by a factor of about 10. When increasing the amount of oil added to this volume, the density seems to increase with increasing oil content. The addition of 11 phr oil (sample 2) may appear to have essentially no effect on the properties or quantitative appearance of the foam. The addition of 33 phr oil (sample 3) slightly reduced the cell size distribution and slightly affected the density. The addition of 100 to 200 phr of oil (Samples 4 and 5) produces a foam of small cell size with a very uniform distribution but significantly denser (heavier) foam. There is no tendency for oil to be released from these foams.

Samples 5-7 and FIG. 3 illustrate the effect of increasing the water content in a foam containing 200 phr oil. The resulting increase in higher water content and isocyanate content results in more foaming, thereby reducing foam density. It is believed that the foam containing 200 phr achieves a density of 110 g / l at about 4 phr water content, which is the same density as oil free sample 1. However, such high oil foams are expected to have lower compressive hardness and cohesive strength than oil free foams of the same density.

Sample 8 is a conventional foam based on polyether polyols to which oil is added. Foams of this conventional type may appear to be unsuitable for oil addition. The foam has an oily feel and releases oil due to the incompatibility of the oil and the polyether polymer.

Example 2

Five foams are diol 1 or diol 1 / monool 1 mixture, isocyanate (MONDUR ^R MR), adhesive resin (WINGTACK 95), catalyst (DABCO ^R 33-LV and DABCO ^R DC-1), surfactant (DABCO ^R DC -5160) and water to prepare a combination as illustrated in Table 3. Two foams contain hydrocarbon processing oil (SHELLFLEX 371).

In a typical preparation, diols, monools and oils, if present, are preheated to 80 ° C. and the adhesive resin is preheated to 150 ° C. Subsequently, the procedure of Example 1 is followed.

Density, elasticity, compressive hardness and hysteresis loss are measured as in Example 1. The results are shown in Table 4.

Foam Formulation Sample Dior ¹ (phr) Monool ² (phr) Oil (phr) Resin (phr) Water (phr) Isocyanate (phr) Amine catalyst (phr) Delayed action catalyst (phr) Surfactant (phr) One 100 0 0 0 One 23.5 0.4 0.3 0.02 9 100 0 100 82 2 37.0 0.8 0.6 0.04 10 100 0 50 100 3 51.8 0.8 0.6 0.04 11 50 50 0 100 3 49.8 0.8 0.6 0.04 12 50 50 0 50 1.5 27.6 0.4 0.3 0.02 13 25 75 0 50 1.5 26.6 0.4 0.3 0.02 ¹ hydrogenated polybutadiene diol (Mn = 3300, f = 1.92) ² hydrogenated polybutadiene monool (Mn = 3800, f = 0.98)

Foam properties Sample Density (g / l) 40% compression hardness (N) Shout (%) History loss (%) Foam Cell Structure One 109 27.8 50 14 Very fine 9 122 5.3 10 32 Very fine 10 111 6.6 10 69 minuteness 11 --- --- --- --- Not growing 12 --- --- --- --- collapse 13 109 0.0 0 96 Very fine

Sample 1 is an example of a high elastic foam and was used for comparison purposes. At a density of 109 g / l, Sample 1 has a compression hardness of 28 N and has good resistance and low hysteresis loss. However, since it does not contain a resin, it does not have adhesive or adhesive properties. Samples 9 and 10 examine the effects of adding a tackifier resin and oil and adjusting the water content to produce a foam of nearly constant density. The results indicate that such foams are much easier to compress than Comparative Sample 1 and have much less elasticity and much more hysteresis loss, as required for pressure sensitive adhesives. Foam Samples 9 and 10 are very good pressure sensitive adhesives; It has good finger adhesion and adheres well to both paper and painted surfaces. It can also be peeled clean from the substrate and provides an example of a removable adhesive foam. Samples 11-13 illustrate the effect of using an oil free polydiene diol / polydiene monool blend. Satisfactory foams are not obtained with Samples 11 and 12. However, by adjusting the preheating temperature, mixing schedule and catalyst concentration, satisfactory foams can be produced in these two formulations. Sample 13 is a very good very soft tacky foam. Sample 13 is a different foam in that it does not show immediate rebound upon compression but fully recovers its initial form and volume when standing. Therefore, the compressive hardness is zero and there is little recovery of the foam after the initial compression in the short time scale test, so the hysteresis loss is almost 100%. In the elasticity test, the foam only dissipates the energy of the falling ball and there is no rebound.

Although the present invention has been described in detail for purposes of illustration, it should not be construed as limiting thereby and all changes and modifications are intended to be included within the spirit and scope of the invention.

Claims (13)

Hydrogenated polydiene diols having a number average molecular weight of 1,000 to 20,000; Aromatic polyisocyanates; Plasticizers; And A polyurethane foam composition derived from a reaction mixture comprising a blowing agent. Hydrogenated polydiene diols having a number average molecular weight of 1,000 to 20,000; Aromatic polyisocyanates; Adhesive resin; Plasticizers; And A polyurethane foam composition derived from a reaction mixture comprising a blowing agent. 3. The polyurethane foam according to claim 1, wherein the plasticizer is compatible with hydrogenated polydiene diols. 4. The polyurethane foam of claim 3 wherein the plasticizer is an oil and / or a hydrogenated polydiene monool having a number average molecular weight of 500 to 20,000. The polyurethane foam according to any one of claims 1 to 4, wherein the polydiene diol has the functionality of 1.6 to 2 hydroxyl groups per molecule and the polyisocyanate has the functionality of 1.8 to 3.0 isocyanate groups per molecule. . The polyurethane foam according to any one of claims 1 to 5, wherein the amount of polydiene diol to plasticizer is in the range of 5: 1 to 1: 4. The polyurethane foam according to claim 2, wherein the amount of polydiene diol to adhesive resin is in the range of 5: 1 to 1: 4. Hydrogenated polydiene diols having a number average molecular weight of 1,000 to 20,000 are combined with aromatic polyisocyanates, blowing agents and plasticizers; A polyurethane foam composition obtained by a process comprising foaming a blended polydiene diol, an aromatic polyisocyanate, a blowing agent and a plasticizer to obtain a polyurethane foam composition. 9. The polyurethane foam composition of claim 8, wherein the hydrogenated polydiene diol, blowing agent, plasticizer and some other components are mixed before blending the mixture with the aromatic polyisocyanate. The polyurethane foam composition according to claim 8 or 9, wherein a surfactant and a catalyst are used in the process. The polyurethane foam composition according to any one of claims 8 to 10, further comprising an adhesive resin. (i) hydrogenated polydiene diols having a number average molecular weight of 1,000 to 20,000 are mixed with a plasticizer, a blowing agent and optionally a tackifying resin, a surfactant and a catalyst to obtain a mixture; (ii) combining the aromatic polyisocyanate with the mixture to obtain a blend; (iii) foaming the blend to obtain a polyurethane foam composition. An article containing the polyurethane foam composition according to claim 1.