CN1443792A - Microsphere thermosetting phenolic resin and its preparation process - Google Patents

Abstract

The present invention discloses a microsphere thermosetting phenolic resin and its preparation process. It is made up by using 100-115 portions of phenol homolog, 100-115 portions of methyl aldehide, 8-10 portions of hexamethenyltetraamine, 50-80 portions of water and 0.6-0.75 portions of polyvinyl alcohol resin through the processes of heating reaction, cooling and discharging material, washing with water and filtering, and drying. Said invented phenolic resin has the good heat-resisting property, its thermolysis temp. can be up to above 500 deg.C. Its toughness is good, strength is high, fineness can be up to 200-1000 meshes, so it has extensive application.

Description

A kind of microspheroidal heat-reactive phenolic resin and manufacture craft thereof

Technical field

The present invention relates to a kind of microspheroidal heat-reactive phenolic resin and manufacture craft thereof, belong to the industrial chemicals field.

Background technology

Develop rapidly along with modern industry, performance requriements to friction materials is also improving constantly, for example in automotive industry, require automobile under the situation of high speed, heavy duty, well to move, this just requires the automobile brake speed reduction unit to possess good use properties, its brake flange (sheet) is heat-resisting, wear-resisting, makes brake steadily; Resol is a kind of important component of making friction materials, owing to itself structural characteristic, make it to have better heat-resisting and high viscosity, its various performances, physical and chemical index directly have influence on the performance quality of friction materials goods, traditional resol poor toughness, heat decomposition temperature is low, but at life-time service below 200 ℃, but surpass 200 ℃ oxidation just obviously takes place, from 300-360 ℃ be thermolysis, this to friction materials at high temperature keep stable friction factor, the degree that reduces wear all is very disadvantageous; According to statistics, 2002, only the friction materials in national automobile industry just reaches 1.5 ten thousand tons with the resol aggregate demand, because of the effect of domestic resin undesirable, wherein most of main external import that relies on, as the U.S., Canada etc., price is very high, therefore how to prepare a kind of higher thermostability that both had, having preferably again, toughness and close-burning resol have very important practical significance with the demand that satisfies the friction materials industry.

Summary of the invention

Purpose of the present invention is intended to overcome the defective of above-mentioned prior art, provides a kind of manufacture craft simple, with low cost, and has superior heat resistance and flexible microspheroidal heat-reactive phenolic resin and manufacture craft thereof.

The objective of the invention is to be achieved through the following technical solutions:

A kind of microspheroidal heat-reactive phenolic resin, it is the phenols homologue 100-115 part by by weight, formaldehyde 100-115 part, hexamethylenetetramine 8-10 part, water 50-80 part, polyvinyl alcohol resin 0.6-0.75 part makes after reacting by heating, cooling blowing, washing filtering, drying.

Make the processing method of above-mentioned microspheroidal heat-reactive phenolic resin, its step is in regular turn:

A), feed intake: phenols raw material, formaldehyde, polyvinyl alcohol resin, hexamethylenetetramine and water are dropped in the reactor, fully stir, and begin heat temperature raising;

B), insulation reaction: when above-mentioned material is warming up to 70 ℃, stop heating, allow material slowly be warmed up to 78-85 ℃, whether material reaches reflecting point in the observing response still, pick up counting from reflecting point, keeping temperature of reaction is 78-85 ℃, and the reaction times is 90-120 minute;

C), cooling blowing: after reaction reaches terminal point, cool to blowing below 40 ℃ immediately;

D), washing filtering: the material of emitting is added 2-3 times of clear water washing, and send into filter and filter;

E), drying: the material behind the above-mentioned washing filtering is carried out drying with drying machine;

F), package storage.

The present invention compared with prior art has following outstanding substantive distinguishing features and marked improvement:

1, the present invention is under the prerequisite that does not change basic raw material phenols and formaldehyde, add special modified component---polyvinyl alcohol resin, in reaction, enter the molecular structure of resol, it is crosslinked to block phenolic hydroxyl group and resol, make the reaction mixture form colloidal state, therefore its thermotolerance, toughness all improve a lot, and have improved wear resistance;

2, common resol synthesis temperature height, wayward its linear lag, molecular weight distribution is wide, and its over-all properties is poor, resin of the present invention adopts low temperature synthetic, be easy to control, linear lag height, molecular weight is concentrated, therefore resistance toheat is good, ordinary resin just begins to decompose in the time of 300 ℃, and resin heat decomposition temperature of the present invention can reach more than 500 ℃, meets the requirement of disc brake pad especially;

3, ordinary resin only is that the order number is low about 180 orders after crushed, and is Polygons or prismatic, particle diameter and proportion inequality, and bad dispersibility will be added solidifying agent during curing, and consumption is more; Sold resin of the present invention is microspheroidal, need not pulverize the order number and can reach the 200-1000 order, the fineness height, particle diameter and proportion are even, good dispersity, and need not add solidifying agent can solidify by direct heating, can reduce about 15% than ordinary resin consumption, the minimizing of organism consumption can fundamentally improve the quality of friction materials, and reduce production cost;

4, ordinary resin production needs vacuum hydro-extraction, and unreacted phenol is difficult to evaporate, and free phenol content height easily discharges the low molecular reaction product of volatility during curing, influence processing characteristics; The present invention has used special suspension method manufacture craft, step of reaction adopts the excessive aqueous solution, both alleviated speed of response, the solvable again unreacted phenol of part that goes reduces free phenol, pass through washing, filtration, drying then after, further reduced free phenol content again, resin is condensation dehydration in forming process, so the release of the low molecular product of non-volatility in the solidification process, possesses the satisfactory stability performance.

Below in conjunction with embodiment technical solution of the present invention is explained further.

Specific embodiments

Embodiment 1

Get phenol 200kg, industrial formol (concentration 37%) 200kg, hexamethylenetetramine 16kg, water 130kg, polyvinyl alcohol resin 1.3kg, add in the reactor, fully stir, and beginning heat temperature raising, when temperature rises to 70 ℃, stop heating, make temperature in the kettle slowly rise to 82 ℃.And whether material reflecting point (be material by deepening clearly, begin to become turbid) occurs in the observation still, when reaching reflecting point, picks up counting, and to keep temperature of reaction be 82 ± 2 ℃, 110 minutes reaction times; Reaction cools to blowing below 40 ℃ rapidly after finishing, the material of emitting is added 2-3 clear water washing doubly, and send into the filter inner filtration, the material behind washing filtering carries out drying with drying machine, dry back microspheroidal heat-reactive phenolic resin finished product, package storage.

Get above-mentioned sold resin and carry out the performance index detection, result such as table 1:

Table 1:

Index name	Currently available products	Product of the present invention
			Free phenol content %	????3.9％	????2.38％
Poly-speed	????85s	????70s
			Softening temperature	????110℃	????102℃
Heat decomposition temperature	????300℃	????526℃
			Average order number	Powdery, 180 orders	Microspheroidal is more than 300 orders

As can be seen from Table 1, free phenol content obviously reduces in the resin finished product of the present invention, and heat decomposition temperature reaches 526 ℃, is much higher than ordinary resin, is particularly suitable for the decomposition temperature of friction materials requirement.

Be made into automobile brake disc type brake facing with above-mentioned sold resin, brake facing carried out performance index detect result such as table 2:

Table 2:

Garden dish temperature ℃		????100℃	????150℃	????200℃	????250℃	????300℃
							Frictional coefficient	The Δ prescribed coefficient	????0.42	????0.42	????0.42	????0.42	????0.42
The ordinary resin product	????0.36	????0.34	????0.33	????0.32	????0.28
						Rosin products of the present invention		????0.39	????0.50	????0.50	????0.50	????0.44
The Δ permissible variation		??±0.08	??±0.10	??±0.12	??±0.12								??±0.12
						Actual deviation	The ordinary resin product	???-0.06	???-0.08	???-0.09	???-0.10	???-0.14
Rosin products of the present invention	???-0.03	???+0.08	???+0.08	???+0.08	???+0.02
							Wear rate	The Δ standard	????0.31	????0.41	????0.66	????1.38	????2.45
The ordinary resin product	????0.50	????0.75	????0.97	????0.99	????1.12
						Rosin products of the present invention		????0.13	????0.14	????0.25	????0.27	????0.30

Can find out obviously that from table 2 the brake facing frictional coefficient that uses resin of the present invention to make all is higher than the ordinary resin product, wear rate is lower than the ordinary resin product, and quality product has raising very significantly.

Embodiment 2

Get cresols 250kg, industrial formol (concentration 37%) 230kg, hexamethylenetetramine 18kg, water 145kg, polyvinyl alcohol resin 1.45kg, add in the reactor, fully stir, and the beginning heat temperature raising, when temperature rises to 70 ℃, stop heating, make temperature in the kettle slowly rise to 83 ℃, and observe whether material reflecting point occurs in the still, when reaching reflecting point, pick up counting, and to keep temperature of reaction be 83 ± 2 ℃ 115 minutes reaction times; Reaction cools to blowing below 40 ℃ rapidly after finishing, the material of emitting is added 2-3 clear water washing doubly, and send into the filter inner filtration, the material behind washing filtering carries out drying with drying machine, dry back microspheroidal heat-reactive phenolic resin finished product, package storage.

Get above-mentioned sold resin and carry out the performance index detection, result such as table 3:

Table 3:

Free phenol content (%)	Poly-speed (s)	Softening temperature (℃)	Heat decomposition temperature (℃)	Average order number (order)
					????2.32	???68	????105	????520	????320

Embodiment 3

Get phenol 330kg, industrial formol (concentration 37%) 330kg, hexamethylenetetramine 30kg, water 240kg, polyvinyl alcohol resin 2.25kg, add in the reactor, fully stir, and the beginning heat temperature raising, when temperature rises to 70 ℃, stop heating, make temperature in the kettle slowly rise to 81 ℃, and observe whether material reaches reflecting point in the still, when reaching reflecting point, pick up counting, and to keep temperature of reaction be 81 ± 2 ℃ 120 minutes reaction times; Reaction cools to blowing below 40 ℃ rapidly after finishing, the material of emitting is added 2-3 clear water washing doubly, and send into the filter inner filtration, the material behind washing filtering carries out drying with drying machine, dry back microspheroidal heat-reactive phenolic resin finished product, package storage.

Get above-mentioned sold resin and carry out the performance index detection, result such as table 4:

Table 4:

Free phenol content (%)	Poly-speed (s)	Softening temperature (℃)	Heat decomposition temperature (℃)	Average order number (order)
					????2.40	???72	????104	????523	????310

Embodiment 4

Get phenol 300kg, industrial formol (concentration 37%) 310kg, hexamethylenetetramine 24kg, water 180kg, polyvinyl alcohol resin 1.85kg, add in the reactor, fully stir, and the beginning heat temperature raising, when temperature rises to 70 ℃, stop heating, make temperature in the kettle slowly rise to 80 ℃, and observe whether material reflecting point occurs in the still, when reaching reflecting point, pick up counting, and to keep temperature of reaction be 80 ± 2 ℃ 115 minutes reaction times; Reaction cools to blowing below 40 ℃ rapidly after finishing, the material of emitting is added 2-3 clear water washing doubly, and send into the filter inner filtration, the material behind washing filtering carries out drying with drying machine, dry back microspheroidal heat-reactive phenolic resin finished product, package storage.

Get above-mentioned sold resin and carry out the performance index detection, result such as table 5:

Table 5:

Free phenol content (%)	Poly-speed (s)	Softening temperature (℃)	Heat decomposition temperature (℃)	Average order number (order)
					????2.31	????69	????108	????510	????325

Microspheroidal heat-reactive phenolic resin manufacture craft of the present invention is simple, finished product has good thermotolerance, performance such as toughness and wear resistance, heat decomposition temperature can reach more than 500 ℃, the fineness height, good dispersity, during curing, need not to pulverize, also need not to add solidifying agent, have energy-conservation, efficiently, pollute advantages such as little, quality can compare favourably with the import expensive goods, its price only is about half of imported product, resin size of the present invention and poly-speed can be controlled as required, can replace traditional common resol, are widely used in phenolaldehyde moulding compound, friction materials, emery wheel, moulding sand for casting, porous plastics, thermal insulation material, refractory materials, the making of materials such as fiberboard.

Claims (2)

1, a kind of microspheroidal heat-reactive phenolic resin, it is the phenols homologue 100-115 part by by weight, formaldehyde 100-115 part, hexamethylenetetramine 8-10 part, water 50-80 part, polyvinyl alcohol resin 0.6-0.75 part makes after reacting by heating, cooling blowing, washing filtering, drying.

2, make the processing method of the described microspheroidal heat-reactive phenolic resin of claim 1, its step is in regular turn:

A), feed intake: phenols raw material, formaldehyde, polyvinyl alcohol resin, hexamethylenetetramine and water are dropped in the reactor, fully stir, and begin heat temperature raising;

B), insulation reaction: when above-mentioned material is warming up to 70 ℃, stop heating, allow material slowly be warmed up to 78-85 ℃, whether material reaches reflecting point in the observing response still, pick up counting from reflecting point, keeping temperature of reaction is 78-85 ℃, and the reaction times is 90-120 minute;

C), cooling blowing: after reaction reaches terminal point, cool to blowing below 40 ℃ immediately;

D), washing filtering: the material of emitting is added 2-3 times of clear water washing, and send into filter and filter;

E), drying: the material behind the above-mentioned washing filtering is carried out drying with drying machine;

F), package storage.