CN101602275B

CN101602275B - Phenolic aldehyde foam double-metal-face chromatic steel sandwich plate and continuous production technology thereof

Info

Publication number: CN101602275B
Application number: CN 200910015329
Authority: CN
Inventors: 孙助海
Original assignee: 孙助海
Priority date: 2009-05-18
Filing date: 2009-05-18
Publication date: 2013-05-01
Anticipated expiration: 2029-05-18
Also published as: CN101602275A

Abstract

The invention relates to a phenolic aldehyde foam double-metal-face chromatic steel sandwich plate with good toughness, comprising an upper metal face chromatic steel plate, a lower metal face chromatic steel plate and a middle phenolic aldehyde foam sandwich plate, wherein the phenolic aldehyde foam sandwich plate comprises the following formula (represented according to parts by weight in the formula): 100 of phenolic resin, 2 to 8 of levelling agent, 3 to 9 of foaming agent, 1 to 5 of catalyst, 0.5 to 1.5 of stabilizing agent and 20 to 30 of curing agent. The production technology of the phenolic aldehyde foam double-metal-face chromatic steel sandwich plate comprises the following steps: firstly, phenol, a formaldehyde solution of 37% and a barium hydroxide water solution of 20% are added into a reactor, stirring is initiated, the temperature is raised to 85 DEG C, a reaction is carried out for 4 to 5 hours at the temperature, a hydrochloric acid water solution is added till the pH value is adjusted to 6.8 to 7,circumfluence is carried out when the temperature is raised to 100 DEG C, oxalic acid is added, then decompression and concentrated dehydration are carried out, sampling is carried out to enable the viscosity of an output material to be 2500 to 3000mPa.(25DEG C), the reaction reaches the final point, and cooling and material discharge are carried out to obtain the phenolic resin.

Description

Phenolic aldehyde foam double-metal-face chromatic steel sandwich plate and continuous production technology thereof

Technical field

The present invention relates to a kind of chromatic steel sandwich plate and production technology thereof, relate in particular to a kind of phenolic aldehyde foam double-metal-face chromatic steel sandwich plate and continuous production technology thereof.

Background technology

Phenol formaldehyde foam is a kind of foamed plastics that is obtained by foaming by phenolic resins, with the polystyrene foam that accounts in early days the market leading position, polyvinyl chloride foam, the materials such as polyurethane foam are compared, it has special premium properties aspect fire-retardant, it is lightweight, rigidity is large, good stability of the dimension, chemical resistance is strong, good heat resistance, difficult combustion, from putting out, low smog, flame resistant penetrates, meet fire without unrestrained thing, cheap, electrical equipment, instrument, building, the insulation heat-insulating heat-preserving material that the industries such as petrochemical industry are comparatively desirable, thereby attract widespread attention.At present, phenol formaldehyde foam has become one of kind with fastest developing speed in the foamed plastics, and consumption figure constantly increases, and range of application constantly enlarges, and research and development is all quite active both at home and abroad.Yet the weakness of phenol formaldehyde foam maximum is that fragility is large, and percent opening is high.

Summary of the invention

The phenolic aldehyde foam double-metal-face chromatic steel sandwich plate and the continuous production technology thereof that the purpose of this invention is to provide a kind of good toughness.

For achieving the above object, the technical solution used in the present invention is:

A kind of phenolic aldehyde foam double-metal-face chromatic steel sandwich plate is comprised of upper and lower metal covering color steel and middle Phonelic foam sandwich board, and it is characterized in that: the compositing formula of described Phonelic foam sandwich board is as follows:

Phenolic resins 100

Levelling agent 2-8

Blowing agent 3-9

Catalyst 1-5

Stabilizing agent 0.5-1.5

Curing agent 20-30

More than be all weight portion in the prescription.

According to described phenolic aldehyde foam double-metal-face chromatic steel sandwich plate, it is characterized in that: the compositing formula of described Phonelic foam sandwich board is as follows:

Phenolic resins 100

Levelling agent 5

Blowing agent 6

Catalyst 3

Stabilizing agent 1

Curing agent 25

More than be all weight portion in the prescription.

A kind of phenolic aldehyde foam double-metal-face chromatic steel sandwich plate production technology is characterized in that: comprise the steps:

At first prepare phenolic resins, in the reactor with agitator, reflux condenser, thermometer, according to phenol: the ratio of formaldehyde=1: 1.0-4.8 adds phenol, 37% formalin and 20% baryta water and begins to stir, be warming up to 85 ℃, reaction is 4-5 hour under this temperature, adding aqueous hydrochloric acid solution transfers pH value till the 6.8-7, be warming up to 100 ℃ of backflows, add oxalic acid, again reduced pressure concentration dehydration, it is 2500-3000mPa (25 ℃) that sampling makes discharging viscosity, this is reaction end, cooling discharging namely gets phenolic resins;

Then according to above-mentioned Phonelic foam sandwich board compositing formula, phenolic resins, levelling agent, blowing agent, catalyst, stabilizing agent are added thermal agitation according to ratio separately in retort, then add curing agent, by mixing bunker mixing debugging, form and mix stoste, namely get the Phonelic foam sandwich board constitutive material, mix stoste and be sprayed onto in the color steel polymerization reaction take place in 30-60 ℃ one-tenth press by muzzle.

Serialization phenolic aldehyde foam double-metal-face chromatic steel sandwich plate material belongs to the organic rigid foam metal of macromolecule sintetics, to be formed through die mould with color steel by the thermosetting phenolic resin foaming, it have lightweight, fire prevention, chance naked light do not burn, smokeless, nontoxic, without do not shrink under drippage, serviceability temperature scope wide (196～+ 200 ℃), the low temperature environment, advantage, the especially good toughness such as not embrittlement.

The specific embodiment

The invention will be further described below in conjunction with the drawings and specific embodiments:

Embodiment one:

A kind of phenolic aldehyde foam double-metal-face chromatic steel sandwich plate is comprised of upper and lower metal covering color steel and middle Phonelic foam sandwich board, and the compositing formula of Phonelic foam sandwich board is as follows:

Phenolic resins 100

Levelling agent 2

Blowing agent 3

Catalyst 1

Stabilizing agent 0.5

Curing agent 20

More than be all weight portion in the prescription.

A kind of phenolic aldehyde foam double-metal-face chromatic steel sandwich plate production technology comprises the steps:

Embodiment two:

Phenolic resins 100

Levelling agent 8

Blowing agent 9

Catalyst 5

Stabilizing agent 1.5

Curing agent 30

More than be all weight portion in the prescription.

The phenolic aldehyde foam double-metal-face chromatic steel sandwich plate production technology is with embodiment one.

Embodiment three:

Phenolic resins 100

Levelling agent 5

Blowing agent 6

Catalyst 3

Stabilizing agent 1

Curing agent 25

More than be all weight portion in the prescription.

Embodiment recited above is described preferred embodiment of the present invention; be not that the spirit and scope of the present invention are limited; under the prerequisite that does not break away from design concept of the present invention; common engineers and technicians make technical scheme of the present invention in this area various modification and improvement; all should fall into protection scope of the present invention; the technology contents that the present invention asks for protection all is documented in claims.

Resin viscosity is very large on foaming condition and foaming quality impact, viscosity is too large, each component is difficult for mixing during foaming, and because poor fluidity, cause rushing the film difficulty, viscosity is crossed and is easy to escape when low, and bubble appears, the bubble phenomenon of collapsing, so viscosity should be controlled between the 2500-3000mPa (25 ℃).When the water content in the resin was too high, owing to steam causes that lather quickness is slow, expansion ratio was little in foaming and the maturing process, otherwise, reduce water content because resin viscosity increases, cause the foaming operation difficulty, research finds that the water yield should be controlled at about about 5%.

On, lower color steel is respectively by upper, unreeling of lower unreeling machine, according to the different templates of different client's needs through different upper, lower press embossing, the stirring of in different retort, heating respectively of phenolic resins and curing agent, work by the resin pump is in order to 2-6: 1 ratio is mixed in stirring-head and is ejected on the molded lower colour film, then go up, lower colour film outer rim is alignd in the forming machine that enters 30-60 ℃, through a series of chemical reaction and upper, lower colour film is bonded together through the high strength die mould and passes through forming press, the size different according to customer requirement, cut by cutting machine again, become finished product.

Serialization is produced phenolic aldehyde foam double-metal-face chromatic steel sandwich plate and is belonged to the New Building Materials industry, be that country greatly develops the project that the energy-saving and environmental protection policy is given special assistance to, be mainly used in insulation, building partition, outer wall composite board, suspended ceiling, abatvoix of the industrial pipelines such as the cold insulation of freezer and petrochemical industry and equipment etc.

Serialization phenolic aldehyde foam double-metal-face chromatic steel sandwich plate material belongs to the organic rigid foam metal of macromolecule sintetics, to be formed through die mould with color steel by the thermosetting phenolic resin foaming, it have lightweight, fire prevention, chance naked light do not burn, smokeless, nontoxic, without do not shrink under drippage, serviceability temperature scope wide (196～+ 200 ℃), the low temperature environment, not embrittlement, be the desirable heat-insulating material of HVAC Refrigeration Engineering.Because the phenol formaldehyde foam rate of closed hole is high, then thermal conductivity factor is low, and heat-proof quality is good, and has a water resisting property and water vapour permeability, is desirable heat insulating energy saving material.Because phenolic aldehyde has benzene ring structure, thus dimensionally stable, rate of change＜1%, and chemical composition stability, anticorrosion anti-aging, particularly ability organic solution, strong acid, weak base corrosion.

In production technology foaming, make blowing agent without freon, meet the International Environmental Protection standard, and contain hydrogen in its molecular structure, oxygen, carbon, during pyrolytic, the gas that overflows is nontoxic, tasteless, and is all harmless to human body, environment, meets the national green environmental requirement.Therefore, phenolic aldehyde foam double-metal-face chromatic steel sandwich plate is optimal fire prevention, thermal insulation, environment-friendly and green insulation material energy-conservation, attractive in appearance

Phenol formaldehyde foam has the different of essence from the material that common macromolecule resin relies on the adding fire retardant to obtain, in fire, do not burn, do not melt, can not distribute toxic smog yet, and have light weight, nontoxic, without burn into insulation, energy-conservation, sound insulation, the advantage such as inexpensive, and foam without freon, non-environmental-pollution, good, the easy construction of processability, its combination property is that present various insulation material is incomparable, it is undesirable to have solved other organic material fire protecting performance, and the inorganic material water absorption rate is large, the easy problem such as skin urtication when " dewfall ", construction.

Below with regard to used blowing promotor, foaming mechanism in the phenol formaldehyde foam preparation with foam is toughness reinforcing is introduced.

One, blowing promotor

1, catalyst/curing agent

Phenol formaldehyde foam generally is to prepare under room temperature or low-heat condition, therefore needs with acid as catalyst, when acid as catalyst, acid can be accelerated the polycondensation reaction between molecular resin, the reaction liberated heat impels blowing agent sharply to gasify, and emulsifying resins is swelled, simultaneously resin solidification.The catalyst of reaction also is the curing agent of resin.The type of curing agent and quantity are extremely important to obtaining good quality froth at ambient temperature.The selection of curing agent should make curing rate and the expansion rate coupling of polymer.Therefore, require used curing agent that curing rate is changed in very wide scope, curing reaction itself can carry out under lower temperature again.

Curing agent divides inorganic acid and organic acid, inorganic acid such as sulfuric acid, hydrochloric acid, phosphoric acid etc.Organic acid has oxalic acid, adipic acid, benzene nitric acid, phenol nitric acid, toluenesulfonic acid, benzene sulfonic acid, mahogany acid etc.The inorganic acid price is low, but curing rate is too fast, and metal is had very strong corrosiveness, therefore the anticorrosion a great problem that becomes in the phenol formaldehyde foam use.Studies show that, can utilize the dilution inorganic acids such as methyl alcohol, ethanol, propyl alcohol to reach inhibition, also can add corrosion inhibitor such as calcium oxide, iron oxide, calcium carbonate, borax anhydrous, alkali and alkaline earth metal ions carbonate and zinc, aluminium etc.Someone has considered to process foam with the alkali nertralizer, but the validity of this method still is confirmed at the end.The research of relevant this respect is also underway.Document was once reported, and used acid naphthalene sulfonic acids phenolic aldehyde not only to play catalytic action but also participated in the condensation reaction of phenolic aldehyde, had reduced sour permeability, and was also just very little to corrosion of metal.Also mention other in the document and reduce foamed material corrosivity method, at first remove volatile matter in the shaped article with vacuum method when making curing agent with hydrochloric acid, use again NH ₃Remove remaining acid or heat treatment under 80-130 ℃ of condition, or add nertralizer etc. at resin formula, these methods make complex manufacturing, and increase cost.

The curing agent that present employing aromatic sulfonic acid is the basis is very general.This is because its corrosivity is little, and has plasticization.Also have organic acid and inorganic acid are mixed use.For guaranteeing to be uniformly dispersed, solid-state organic sulfonic acid should be made into the aqueous solution of high concentration during use, the concentration of general solution is advisable at 40-65%.

2, blowing agent

Blowing agent is that the plastic foamed method in source of foaming power in the plastic foamed moulding generally is divided into mechanical foaming, physical blowing and chemical blowing.Mechanical foaming is the strong agitation by means of machinery, sneaks into with making gas uniform and forms bubble in the resin.Physical blowing then is by means of the change that is dissolved in the blowing agent physical state in the resin, forms a large amount of bubbles.More than two kinds of foaming be physical process fully, any chemical change does not occur.Chemical blowing is to make CBA generation chemical change in the foaming process, thereby decomposes and produce a large amount of gases, and foaming process is carried out.Kind and the consumption of blowing agent have material impact to foaming effect.It directly affects foam density, and then has influence on physics, the mechanical performance of product.In addition, use blowing agent to make foam have a large amount of spherical micropores, foam flame resistance and toughness improve.

According to the Foaming of phenolic resin reaction mechanism, great majority carry out with physical foaming method.Physical blowing agent divides inert gas and low-boiling point liquid two classes.The blowing agent that phenol formaldehyde foam is commonly used is the volatile liquids of various boiling points between 30-60 ℃, such as freon, chlorinated hydrocabon, pentane etc.The blowing agent overwhelming majority who uses in present scientific research and the plant produced remains HCFC, and is wherein the most extensive with (mol) mixture use in 1: 4 of freon-21 with freon 1.Fluorochlorohydrocarbon blowing agent effect is very good, but fluorochlorohydrocarbon can destroy the ozone layer of atmosphere, so limited use and begun to select substitute.In recent patent, for reducing the harm to atmospheric ozone layer, select to endanger little fluorochlorohydrocarbon, such as CF32CF2CHC12, HCF2CF2CEt, be called as the blowing agent that does not consume ozone.The somebody adopts the use amount that reduces the fluoride blowing agent, adds the part substitute, mixes use such as F-11 and pentane.The most promising inert gas blown agent carbon dioxide, the nitrogen etc. of surely belonging in new substitute.They are nontoxic, pollution-free, and ozone-depleting coefficient (ODP) is zero, and (GwP) is very little for the greenhouse effects coefficient, does not fire, and be cheap and easy to get, be the focus of freon substitute research, but difficulty is higher.The good news is bibliographical information, the researcher of the Asahi chemical company of Japan uses CO ₂Replace fluorochlorohydrocarbon to make to produce the blowing agent of phenolic foam material, respond well.They are by phenolic aldehyde copolymer resins (containing methylolurea) and blowing agent CO ₂Reach the awake foamed material of phenol that catalyst mixture makes.Its airtight air vent content is 96.0%, and hole diameter is 190 μ m, and thermal conductivity (JISA1412) is 0.0231Kcal/m.h. ℃, CO ₂Content is 5.2%, and brittleness (JIS A9511) is 11%.The most frequently used with carrene in the chlorinated hydrocabon, its chemical property is comparatively stable, gas forming amount also is higher than fluorochlorohydrocarbon, so in recent years the replacements fluorochlorohydrocarbon used of existing many producers or the two and usefulness.In plastic foamed industry, select low boiling aliphatic alkane G4-G7 mixture such as pentane as blowing agent, but its effect is undesirable, also has inflammable danger.Sometimes the way by several blowing agents and usefulness solves the problem that blowing agent vapourizing temperature and resin solidification reaction speed are complementary, and blowing agent is when vaporization like this, and resin has had suitable viscosity, thereby is conducive to the formation of foam structure and stable.

CBA also has application, and such as blowing agent H (N, N one dinitrosopentamethlyene tetramine), it meets strongly decomposition of acid, discharges nitrogen, thereby makes resin expanded.

3, surfactant

Contain hydrophilic-structure and hydrophobic structure in the molecule of surfactant, capillary effect with interface trend and reduction liquid resin, make the emulsifying raw material that hydrophily and hydrophobicity differ greatly in the foamed plastics become homogeneous system, each component fully contacts, and various reactions can be carried out more evenly.Though the consumption of surfactant is little, be the 2-6% of resin only, it is very large on foam process and properties of product impact.It can guarantee that each component fully mixes in the foaming process, forms evenly fine many foam structures and stable rate of closed hole, can also accelerate course of reaction, shortens hardening time, and to the compression strength of foamed product, abscess-size etc. all have larger impact.

The foam plastic foaming moulding divides three phases usually.Phase I is to form a large amount of evenly fine and closely woven nuclei of bubbles in the melt of foaming matrix or liquid, and then expand into the foam with requirement foam structure, and by heating, solidifying and setting obtains foam plastic product at last.The foaming phase I be to make take blowing agent as decentralized photo, resin is the emulsion of continuous phase, in resin, form be evenly distributed in a large number, blowing agent drop (nuclei of bubbles) that particle diameter is small.As with high-speed stirred blowing agent being distributed in the resin merely, this dispersion is extremely unstable, destroys easily.Surfactant can reduce interfacial tension, makes dispersion stable at thermodynamics.At this moment surfactant has played the effect of emulsifying agent or foam stabilizer.When under high-speed stirred, when adding curing agent in the emulsion of phenolic resins and blowing agent, the phenolic foam moulding has entered second stage.A-stage resin generation condensation reaction under the curing agent effect, be converted into the B-stage resin stage, final curing is C-stage resin, a large amount of reaction heat that the while resin condensation discharges make the blowing agent droplets vaporize, and foamed material is in retrogradation, and volume increases rapidly, original emulsion has been transformed into foam, this foam is unsettled, and established bubble can continue to expand, and also may merge, subsides or break.There is not solidifying and setting front surface activating agent to play a part stable foam at phenol formaldehyde foam.

Compatibility between each component of phenolic foam is relatively poor, so select surfactant more will consider its emulsifiability.Good emulsifiability can improve the uniformity coefficient that each component is mixed, and is conducive to form evenly fine foam structure, and can accelerates course of reaction, shortens hardening time.This external surfactants also must keep stable to the highly acid of curing agent.Although it is a lot of to be used for the kinds of surfactants of phenolic foam, the nonionic surface active agent effect is best, and commonly used have 1. aliphatic alcohol polyethenoxy, a polyoxypropylene ethers; 2. APES class is such as the addition product of nonyl phenol and oxirane; 3. the block copolymer of polysiloxanes, polyoxyethylene, polyoxypropylene, this class surfactant not only has good foam stabilization performance, and extremely strong emulsification is arranged.

Also there is in recent years the researcher to adopt the kinds of surface active agent intermixture to obtain having the foam of particular characteristic, makes the high-hydroscopicity foam such as the surfactant that the usefulness silicone such as Ikeda justice is grand mix with neopelex.

Two, foam Research on Toughening

The structural weak link of phenolic resins is the easy oxidation of phenolic hydroxyl group and methylene.Its foam percentage elongation is low, and matter is crisp, and hardness is large, not anti-bending.This has limited the application of phenol formaldehyde foam greatly, so be very necessary to the toughness reinforcing of foam.Phenol formaldehyde foam toughness reinforcing, can realize by following several approach: 1. flexibilizer outside system adds, the mode by blend reaches toughness reinforcing purpose; 2. by the chemical reaction of resol and flexibilizer, reach toughness reinforcing purpose; 3. with the modified phenol replacement phenol synthesis resin of part with the flexible chain.

1, adds outer flexibilizer

This modification mode requires resin and toughened system must have certain compatibility, could improve its fragility, improves toughness and compressive property, can be according to the compatibility between the solubility parameter δ prediction organic compound.The enforcement of this modification mode generally is to carry out as follows.Then at first synthetic common resol adds modifier in system, dehydration, foaming.This class modifier is commonly used three classes.

The first kind is rubber elastomer modifier.Rubber toughened phenolic resins belongs to physics blending modification, but because elastomer is with activated end group (such as carboxyl, hydroxyl etc.) and two key usually, can with resol in methylol occur in various degree connect the school or block copolymerization is reacted.These rubber-like elastomeric segments generally can be separated out from matrix in resin solidification and foaming process, form physically the island two phase structure.The fracture toughness of this rubber toughened thermosetting resin and foam has by a relatively large margin raising compared with not toughness reinforcing resin and foam.Rubber commonly used has butyronitrile, butylbenzene, natural rubber and nbr carboxyl terminal and other to contain the rubber of active group.Toughness reinforcing effect is also relevant with blend ratio etc., and rubber mass does not reach effect very little, if but rubber content is higher, affect heat resistance, also can affect the compatibility between phenolic aldehyde rubber simultaneously.The addition of rubber generally should be controlled between the 5-20%.

Equations of The Second Kind is thermoplastic resin.What be used for the phenol formaldehyde foam modification has polyvinyl alcohol, a polyethylene glycol etc.Hydroxyl in the polyvinyl alcohol molecule might with phenol-aldehyde condensation polyme in methylol generation chemical reaction, form graft copolymer.Polyvinyl alcohol modification phenolic resins can improve the compressive strength of foam.According to the literature, foam compression intensity is relevant with the addition of polyvinyl alcohol.Add the amount of polyvinyl alcohol very little, compressive strength improves not obvious; The polyvinyl alcohol that added volume can cause sticking pot, makes reaction be difficult to proceed.The addition of polyvinyl alcohol is that the 1.5-3% of phenol weight is comparatively suitable.

Polyethylene glycol also is the effective flexibilizer of phenolic resins.OH in the polyethylene glycol may be combined by the OH in resin, but reaction is difficult under alkali condition.OH in the polyethylene glycol and the OH in the resin be possibility forming section hydrogen bond also, makes to import long flexible ether chain in the resin, thereby plays toughness reinforcing effect.The polyethylene glycol of the human different molecular weights such as Ge Dongbiao series is come toughness reinforcing foam, finds that modified effect increases along with the increase of molecular weight polyethylene glycol, and molecular weight is to reach peak value at 1000 o'clock, and the then increase along with molecular weight polyethylene glycol reduces.Given conclusion is: along with the increase of molecular weight, the polyethers flexible chain that imports in the phenolic resins is long first, is conducive to hot strength and elongation at break and increases; But molecular weight polyethylene glycol was greater than 1000 o'clock, because it is certain adding the quality of people's polyethylene glycol, the shared ratio of its strand two terminal hydroxy groups reduces relatively, so that the probability of the methylol of hydroxyl and phenolic resins reaction reduces, has affected the modified effect of polyethylene glycol.The foam toughness of the cetomacrogol 1000 that molecular weight is moderate and 800 modifications is best.

The phenol formaldehyde foam of polyethylene glycol toughening modifying is compared with pure phenol formaldehyde foam, and not only good stability of the dimension, compressive strength are high, apparent density is moderate, and the abscess rate of closed hole is higher, the size is even, fine and close, and easily processing cutting, section without or few chip.Haloflex (CPE), polyvinyl chloride (PVC) toughened resin and foam also have report in addition.

The 3rd class is small-molecule substance such as ethylene glycol.After the toughness reinforcing foam of ethylene glycol is novolak resin, adds by a certain percentage ethylene glycol and mix, add successively stabilizing agent, blowing agent, equal infusion, stir, then add curing agent, vigorous stirring, pour rapidly group's mould foaming in the ready mould into, the demoulding gets final product behind its completion of cure.

Someone is according to the difference of the infrared spectrogram of pure phenol formaldehyde foam and glycol-modified phenol formaldehyde foam (ethylene glycol content is phenol amount 15%), infer that ethylene glycol may be under acid catalysis, partly or entirely generate the derivative of glycerine alcohols, participated in main reaction.The adding of ethylene glycol can improve the performance of phenol formaldehyde foam to a certain extent, improves its compressive strength, improves its fragility, and don't loses too much its anti-flammability, and optimum amount is 10-15 part/100 part resins.This moment, its oxygen index (OI) was 37-38, and compressive strength is 0.40MPa, and density is 0.059g/cm3, and is as shown in table 1.

Table 1 foaming properties and ethylene glycol addition

	A	B	C	D	E	F
							Ethylene glycol/w%	25	20	15	10	5	0
Density/g.cm ³	0.064	0.06	0.059	0.058	0.056	0.062
							Compressive strength/MPa	0.30	0.35	0.40	0.37	0.38	0.31
Oxygen index (OI)	35	37	37	38	38	40

Adding chopped glass fiber also is outer toughness reinforcing a kind of method.Chopped glass fiber belongs to inorganic material, and is colourless under the normal temperature, tasteless, nontoxic, easy and phenolic resins mixing.Chopped glass fiber is after with coupling agent treatment, and with the phenolic resins blend, then phenolic foam is made in foaming.Chopped glass fiber content sees Table 2 to the impact of modified phenolic foam plastic main performance.

The chopped broken fine content of table 2 and phenol formaldehyde foam performance

Chopped glass fiber/w%	0	3	4	5	6	8	10
								Unit weight/kg.cm ³	60	60	60	60	62	68	80
Fragility mass loss/%	40.0	28.0	25.0	22.0	21.0	17.7	15.0
								Oxygen index (OI)	45	45	46	48	48	50	50
Compressive strength/MPa	0.20	0.25	0.26	0.28	0.31	0.39	0.43

As shown in Table 2, increase along with chopped glass fiber content, the compressive strength of phenolic foam obviously improves, unit weight increases, fragility reduces, and oxygen index (OI) raises, but the viscosity of blend raises along with the increase of chopped glass fiber content, make foam process be difficult to control, so the content general control of chopped glass fiber is below 10%.It is toughness reinforcing that document has reported that also the organic substances such as dioctyl phthalate, tricresyl phosphate are used for foam.

2, chemical toughness reinforcing resol

The chemistry toughening modifying method is to add modifier when synthetic A-stage resin, by flexible chain in the chemical reaction grafting of phenolic hydroxyl group and methylol, thereby obtains the modification A-stage resin of intrinsic toughening, and this method of modifying will be got well than the effect of blend method.

Polyurethane-modified phenol formaldehyde foam is a kind of good chemical method for toughening, has carried out series of studies in Japan, the U.S., has obtained preferably achievement.See following 2 kinds of modes from the method that adopts: 1. with furfuryl alcohol resin, arylamine polyalcohol etc. as the polyol the polyurethane component, phenolic resins, polyisocyanates (MDI, PAPI) and above-mentioned various polyalcohol are mixed, and the auxiliary agents such as adding blowing agent carry out composite foamed.2. polyethers, the synthetic end of the pure and mild isocyanates of polyester polyols are the performed polymer of a NCO group, mix with phenolic resins, blowing promotor again, carry out composite foamed.

In polyurethane-modified phenol formaldehyde foam preparation process, no matter adopt which kind of method of modifying, its reaction mechanism is consistent.Mainly contain two kinds of reactions and occur, 1. the hydroxyl of the polyol in isocyanate groups and the component carries out crosslinked or chain extending reaction; 2. the methylol in isocyanate groups and the resol carries out cross-linking reaction.The result of two kinds of reactions has introduced the pliability segment in phenolic aldehyde rigid molecule structure, fundamentally changed the rigid molecule structure of phenolic resins, thereby has improved the toughness of foamed product, has reduced fragility; Introduced simultaneously the characteristic of polyurethane, as improving rate of closed hole, reduced water imbibition, accelerated curing reaction speed, moulding is fast, has also improved the intensity of goods.

Take the polyethylene glycol reaction as 1000 of TDI and molecular weight, synthetic performed polymer modified phenolic foam with a NCO group, its performance is as shown in table 3.

Table 3 TDI modified poly (ethylene glycol) toughening metlbond foam performance

Compressive strength/MPa	Density/kg.cm ³	Water absorption rate/%	Oxygen index (OI)
				0.288	0.1771	14.39	38.3

3, with the modified phenol replacement phenol synthesis resin of part with the flexible chain

The 3rd class method of modifying is to replace phenol and formaldehyde condensation with the toughness material part that contains with the similar functional group of phenol, thereby reaches toughness reinforcing purpose.The modifications such as bibliographical information resorcinol, orthoresol, paracresol, hydroquinones are arranged.Addition is controlled at 0.2-10%, can reduce foam brittleness, improves intensity and the toughness of goods.Alkyl phenol and cashew nut oil modified report arranged also.The cashew nut shell oil primary structure is monoene or diolefin long-chain with 15 carbon between phenol, so the feature of the existing phenolic compound of cashew nut shell oil, and the flexibility of aliphatic compound is arranged again, uses its modified phenolic foam, and toughness has clear improvement.

Attempt with tung oil and modification of flax oil phenol also someone, the conjugated triene in the tung oil under acid catalysis with the reaction of phenol generation kation alkyl, wherein residual two keys are because empty inhibition effect, the probability of participating in reaction is very little.Product under base catalysis further with formolite reaction, generated tung oil-modified resol.Linseed oil is the octatecatrienoic acid glyceride, and three two keys are arranged in its molecular structure.Under the effect of catalyst, alkylated reaction occurs at two keys of linseed oil in the carbon atom on the ortho para of phenol, synthesis modification phenol, then modification phenol and formaldehyde copolymerization, submissive alkyl chain has linked the phenolic aldehyde strand of fragility not, has effectively improved phenol formaldehyde foam fragility.

Claims

1. phenolic aldehyde foam double-metal-face chromatic steel sandwich plate production technology, described phenolic aldehyde foam double-metal-face chromatic steel sandwich plate is comprised of upper and lower metal covering color steel and middle Phonelic foam sandwich board, and the compositing formula of described Phonelic foam sandwich board is as follows:

More than be all weight portion in the prescription;

It is characterized in that, comprise the steps:

Then according to described Phonelic foam sandwich board compositing formula, phenolic resins, levelling agent, blowing agent, catalyst, stabilizing agent are added thermal agitation according to ratio separately in retort, then add curing agent, by mixing bunker mixing debugging, form and mix stoste, namely get the Phonelic foam sandwich board constitutive material, mix stoste and be sprayed onto in the color steel polymerization reaction take place in 30-60 ℃ one-tenth press by muzzle.