CA1077643A

CA1077643A - Diphase polymeric substrates for electroless metal deposition

Info

Publication number: CA1077643A
Application number: CA255,541A
Authority: CA
Inventors: Edward J. Leech
Original assignee: Kollmorgen Corp
Current assignee: Kollmorgen Corp
Priority date: 1975-07-25
Filing date: 1976-06-23
Publication date: 1980-05-13
Also published as: IT1066020B; AU503695B2; DE2633094C3; AU1525576A; ZA763010B; IL50093A; JPS5215569A; FR2333024B1; JPS5953295B2; ATA545376A; IL50093A0; NL185935B; NL7608242A; DE2633094B2; NL185935C; DE2633094A1; CH636631A5; FR2333024A1; GB1531826A; AT362008B

Abstract

Abstract of the Disclosure - New polymeric substrates for the electroless deposition of metal thereon. The substrates of the invention result from the polymerization of liquid mixtures comprising a liquid precursor of a polymer that is relatively susceptible to oxidative attack and a liquid precursor of a polymer that resists oxidation.

Description

Organic coatings and materials whose surfaces may be provided with electroless metal deposits having commercially acceptable adhesion, that is, peel strengths of at least seven pounds per inch of width, have hereto- :
fore fallen into two distinct categories according to the method of preparing them and the requisite chemical treatment for insuring sufficlently adherent electroless metal plating on them.
A first type includes such products as platable grades of ABS and polypropylene, the adhesives disclosed in Stahl et al U.S. Patent No. 3,625,758, issued December 7, 1971, and epoxy/phenolic blends with poly-butadiene, such as the Beiresdorf technical materials.
Materials of this first type typically contain a dispersed dc/

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~ 1 107764 ' ~- 1 ¦ phase of butadiene or acrylonitrile butadiene agglomerates

2 ¦ within a matrix of materials such as epoxy/phenolic blends.
8 ¦ The material of the dispersed phase of such substrates is 4 I readily degraded by o~idizing agents, such as chromic or 6 I permanganate solutions, while the matrix phase is less 6 ¦ reactive to such agents. Following chromic or permanganate 7 ¦ treatment, the substrate surface is microporous, resulting in 8 ¦ greatly increased surface area, and is suitable for further ~¦ processing in known electroless metal plating procedures.
10¦ Substrates of this type, i e., heterogeneous, dispersed 11 I phase-matrix phase materials, have previously been prepared 12 ¦ by masticating prepolymer of the dispersed or reactive phase ~
¦ material in solvent down to the desired molecular weight or ~-1~ ¦ chain length, and then blending the mast~cated prepolymer 15 I with t~e cont~nuous phase or matrix phase materials in copious 16 I amounts of solvent. Such substrate materials normally comprise 17¦ from 65 to 80 weight percent solvent prior to their application 18¦ to base substrates as coatings, and, following solvent i91 evaporation, typically comprise about 60 weight percent of ' I unsaturated rubber as the dispersed phase and about 40 weight ¦ U l percent of a thermosetting plastic matrix.
. æ. ¦ A second general type of resinous substrates, such as 23 epoxy and polysulfone, includes materials having an otherwise 2~ homogeneous single phase but with areas of differing crosslink density. Forming a microporous surface on such substrates ; 26 requires a mandatory step preceding oxidation: polar and a7 stxained sites that are selecti~ely attacked in the-oxidation . .",'''' ,''. .

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i ' I 1~77643 1 ¦ step must be created, usually by contacting the homogeneous 2 1 substrate with a strong organic solvent, to permit preferential

3 ¦ attack at areas having a lower density of crosslinks.

4 It is the object of this lnvention to provide improved processes for forming substrates for adherent metallization 6 ant improved substrates for the elec~roless deposition of 7 metals thereon.
8 It was believed that if a diphase material could be 9 ~ormed as a result of micro phenomena, rather than as a result of physically masticating prepoiymer of a degradable lt material and then effecting a dispersion of this material in 12 a matrix of a second material by blending, the diphase material 13 would be more uniform and the process for making it would 14 be more efficient.
Polymers having ethylenic unsaturation, i.e., double 16 bonds that are not of the resonant or benzene-type and that li will participate in chemical reactions in a fashion analogous 18 to the double bond in ethylene, are relatively susceptible 19 to oxidative degradation, especially compounds having con~u-gated touble bonds. Polymers having essentially no ethylenic 2t unsaturation are rela~ively resistant to oxidation. According 22 to the invention, totslly liquid mixtures having at least two Z3 liquid constituents are polymerized to yield a diphase polymer, 24 with at least one of the constituents being a liquid precu~sor of a polymer having ethylenic unsaturation and with at least 26 one li~uid precursor Df a polymer having essentially no `
27 ethylenic unsaturation.
28 The precise fonm or the liquid precursors is not critical.
29 Thus, they may be monomeric, dimeric, or even longer in chain 3 - _ .. .

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1 ¦ length, so long as they remain liquid, wlll form the requisite 2 ¦ mixtures with each other, and will polymerize to yield diphase 3 ¦ polymers according to the invention.
¦As detailed below, liquid mixtures of the sort iUst des-cribed may be polymerized to yield materials that comprise a dispersed phase rich in polymer having ethylenic unsaturation 7 and a continuous phase rlch in polymer having essentially no ethylenic unsaturation, with a polymer having conjugated double 9 bonds being preferred for the dispersed phase. When such a polymeric material is contac~ed in known fashions with, for Il example, chromic or permanganate solutions, the portions rich 12 in ethylenic unsaturation are preferentially attacked and de-1 13 graded, resulting in a microporous structure interconnected by 14 portions rich in polymer having essentially no ethylenic IS unsaturation.
16 Substrates according to the invention include surfaces i of the heterogeneous type, some of which require only 18 oxidati~e treatment to increase the surface area of the substrate by rentering it microporous ant some of which require pre-treatment with an organic solvent.
21 A heterogeneous, dispersed phase-matrix phase type of substrate may be obtained as described herein with the followin 23 advantages over the previously known heterogeneous substrates:
24 no tèdious and energy-consuming mastication and blend~ng procedures are required and far less solvent is necessary, 26 thereby decreasing cost, energy consumption in meeting drying i requirements, and waste of materials.
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, Whether heterogeneous substrates requiring only oxidation treatment to render the surfaces microporous are desired or those requiring pretreatment with an organic solvent prior to oxidation are preferred, subs-trates resulting from processes described below are generally obtained in a more efficient fashion than previously known substrates and impart enhanced proper-ties to finished metallized articles.
In a preferred embodiment of the invention, heterogeneous surfaces comprising an unsaturated rubber-rich phase dispersed in a continuous phase of thermo-setting resin are formed by taking advantage of micro phenomena, rather than by effecting a physical dispersion as in the previously known process. A totally liquid mixture is formed of at least two constituents: one of the two minimum ingredients must be a liquid which, upon polymerization, will yield an unsaturated rubber suscep-tible to oxidative degradation; the other minimum ingred-ient must be a ~iquid which, upon polymerization, will yield a thermosetting resin that is relatively impervious to oxidation. And finally, the liquid mixture must, upon polymerization, result in separation of the two polymer products to a sufficient extent to form a diphase solid con8isting of a di6persed phase rich in unsaturated rubber and a continuous phase rich in resin.
In order to provide a suitable platable surface ; ~ -for the deposition of electroless metal, it is also necessary that the resultant surface be adherent to the metal. And if the overall objective is the formation of printed circuit boards, the final product having the metallized surface must be capable of high temperature performance, for example to dc/

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' ' . : ' ` ' ~ 77643 ermit soldering operations.
Experimental work specifically directed to the use of the invention in making printed circuit boards has demonstrated that the preferred embodiment may be achieved by using as one component a highly polar liquid precursor that will polymerize to yield a rubber having ethylenic unsaturations and a highly functional liquid precursor of a thermosetting resin as a second component. As a general rule, it has been found that combinations of lower polarity unsaturated rubber precursors and low functionality resin precursors lead to polymer products exhibiting unreliable adhesion to electroless metal or inferior high temperature performance, rendering them unsuitable in printed circuit applications. Combinations of lower polarity unsaturated rubber precursors and resin precursors of high functionality tend to result in a lack of compatibility of the two components, which is usually manifested by unacceptable separation.
I have found that certain liquid mixtures comprising liquid carboxyl-terminated acrylonitrile butadiene, having also carboxyl groups randomly dispersed along the chain length or amine -terminated acrylonitrile butadiene, such as B.F. Goodrich's ATBN; highly functional liquid epoxies, such as epoxy novolacs or cycloaliphatic epoxies or mixtures thereof; and, optionally, liquid phenolic novolac yield, upon polymerization, improved resinous surfaces for later adherent metallization in electroless ---metal deposition baths.
In one particular aspect the present invention provides a process for producing a diphase polymeric surface for the adherent electroless deposition of metal thereon, the two phases consisting of a dispersed first phase rich in polymer having ethylenic unsaturation and a continuous second phase rich in polymer having substantially no ethylenic unsaturation, , ` -6-10i77643 lid process comprising the steps: (a) admixing at least two liquid constituents, the first of said constituents comprising a liquid precursor of a solid polymer having ethylenic unsat-uration and the second of said constituents comprising a liquid precursor of a solid polymer having substantially no ethylenic unsaturation; and (b) polymerizing the admixture of step (a) to yield a solid, two phase polymerization product comprising a dispersed phase rich in the polymerization product of said first constituent and a continuous phase rich in the polymerization product of said second constituent.
In another particular aspect the present invention provides a process for producing a diphase polymeric surface for the adherent electroless deposition of metal thereon, the two phases consisting of a dispersed first phase rich in a polymer having ethylenic unsaturation and a continuous second phase rich in a polymer having substantially no ethylenic unsaturation, said process comprising the steps: (a) forming a liquid mixture comprising two liquid constituents, the first said constituent being a liquid precursor of a solid polymer having ethylenic unsaturation consisting of from about 45 to ; about 65 percent by weight of a highly polar liquid carboxyl- .. : -terminated acrylonitrile-butadiene having carboxyl groups : dispersed along the chain length, and the second said constituent being a liquid precursor of a solid polymer having substantially .
no ethylenic unsaturation consisting of from about 20 to about 40 percent by weight of at least one component selected from -the group consisting of liquid novolac resins and liquid cycloaliphatic epoxy resins; and (b) polymerizing the admixture :
of step (a) to yield a solid, two phase polymerization product : :
comprising a dispersed phase rich in the polymerization product of said first constituent and a continuous phase rich in the polymerization product of said second constituent.

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~077643 In a further particular aspect the present invention provides an article for the electroless deposition of adherent metal thereon from an electroless metal deposition bath, in which at least a portion of the surface of said article has been coated with a layer of two-phase polymer susceptible to oxidative attack, said polymer comprising a dispersed phase rich in the polymerization product of a first liquid constituent comprising a liquid precursor of a solid polymer having ethylenic unsaturation, and a continuous phase rich in the polymerization product of a second liquid constituent comprising a liquid precursor of a solid polymer having substantially no ethylenic unsaturation. .
In yet a further particular aspect the present invention provides an article for the electroless deposition of adherent metal thereon from an electroless metal deposition bath, in :
which at least a portion of the surface of said article has :; been coated with a layer of a two-phase polymer susceptible to :
.i oxidative attack, said polymer comprising a dispersed phase ; rich in the polymerization product of a first liquid constituent comprising a liquid precursor of a solid polymer having ethylenic unsaturation consisting of from about 45 to about 65 percent by weight of a highly polar liquid carboxyl-terminated acrylonitrile-butadiene having carboxyl groups dispersed along the chain length, and a continuous phase rich in the polymer-ization product of a second liquid constituent comprising a liquid precursor of a solid polymer having substanti.ally no ethylenic unsaturation consisting of from about 20.to about 40 percent by weight of at least one component selected from the group consisting of liquid novolac resins and liquid cycloaliphatic epoxy resins.
The figures are scanning electron microscope photomicro-graphs obtained at the magnification and tilt indicated for each specimen and illustrate the grain structures, or surface charac-.

-6b-' ' . ' 1~776~3 teristics, of the substrates.
Figure 1 shows an untreated, heterogeneous substrate according to the invention;
Figure 2 is a photomicrograph of a preferred prior art heterogeneous substrate, also untreated;
Figures 3 and 4 illustrate a Figure 1 surface following chromic treatment in the known fashion;
Figure 5 is a Figure 2 surface following chromic oxidation;
Figures 6 and 7 are Figure 1 surfaces following oxidative attack by contacting with permangana~e solution; and Figure 8 is a Figure 2 surface that haæ been permanganate treated. -The content of the carboxyl acrylonitrile butadiene in the liquid mixture may vary from about 45 to about 65 weight percent of the mixture. Significantly more than 65 weight percent generally results in a polymer that is overly rubbery and weak. Significantly less than 45 we~ght percent content renders the resultant polymers almost totally resistant to oxidation agents presently preferred by practitioners. The preferred -content of this component is from about 50 to about 60 ; weight percent.
The highly functional epoxy content of the liquid mixture may range from about 20 to about 40 weight percent.
Suitable epoxies include liquid epoxy novolacs and liquid cycloaliphatic epoxies having a high functionality, or mixtures of such epoxies.
Phenolics may optionally be included in the liquid mixture. A preferred liquid phenolic resin is phenolic , I .

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1 ¦ novolac, and it may be present in amounts ranging from 2 ¦ zero to aboue 35 weight percent.
8¦ Utilization of the liquid mi::tures described to form ~¦ resinous surfaces for adherent me~allization requires their ~¦ polymerization. This is preferably achieved through the G¦ addition of a catalyst, curative, accelerator or mixture 7 thereof to the liquid mixture. Preferred agents inclute 8 dicyandiam~de, menthane diamine, ~ N,N,N',N'- tetramethylbutanediamine, and stannous octoate.
Polymerizable mixtures according to the pr~eferred 11 embodiment will typically consist of about~85 weight perc~t 12 solids, with the remainder attributable to minor solvent 13 content of the ingredients and catalyst. A preferred method 14 of forming polymerized substrates from the liquid mixtures 16 includes the step of curtain coating a base with the liquit 16 prior to polymerization, and I have found that reducing the 17 sol:~ds content to about 70 weight percent facilitates this 18 processing step. Where the curtain coating step is used, i9 my yreferred solvent is ethylene glycol monomethyl ether ~: A 20 (methoxyethanol), such as methyl-Cellosolve~
21 Forming the initial liquid polymerizable mixture 22 containing from about 45 to about 65 weight percent 23 carboxyl-terminated acrylonitrile butadiene, also having 24 carboxyl groups along its chain length, from about 20 to 2~ about 40 weight percent of highly functional epoxy novolac 26 or cycloaliphatic epoxy or a mixture thereof, and from zero 27 to about about 35 weight percent phenolic novolac may be ,,' . -I

1 1(~776 1 conveniently done at room temperature or with slight warming 2 to facilitate mixing.
8 The above-described mixtures may be utilized in any 4 number of ways to provide polymeric surfaces for adherent ~ metallization. The entire article may be formed of 6 polymerization products according to the above, or the 7 article to be metal plated may be provided with just a 8 surface coating of such polymers.
9 If the articles to be metallized are to be provided with a layer of the disclosed polymers, such layers may be applied 11 to a base in many ways. Two basic options include: applying 12 the liquid mixture diree~ly to the base and then precuring 13 the mixture prior to conducting the metal de~osition process;
1~ and forming thin precured sheets from the liquid mixture for later lamination to the article to be metallized. For 16 example, panel size articles (typically about two square 17 feet in area), including laminates, may be coated with the 18 liquid mixtures by, for example, curtain coating, roller 19 coating or dip coating. The mixtures may then be cured or 1 20 polymerized by heating, for example via infrared or in a 1 21 convection oven. Sheet size laminates (typically about 22 twelve square feet in area) are most efficiently provided 23 with a coating of such materials by forming precured sheets 24 of a polymer, for exemple by coating and precuring the 2$ mixture on a release sheet, and then laminating the polymer a~ with a base material.

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1C~77643 If polymeric surfaces according to the invention are to form a layer on a base of a different material, fully cured layers of the polymer preferably have a minimum thickness of about 0.75 mil and a maximum thick-ness of about 1.5 mil, ~ith a preferred thickness of about 1 mil. In contrast with the previously known platable surface coatings, which have low solids - high solvent contents and will provide a final 1 mil-thick coating over about 300-350 square feet of base material per gallon, the low solvent of the instant polymeric coatings permits coverage in the amount of 850-950 square feet of --base per gallon per mil.
Diphase polymeric surfaces formed according to the instant invention may be rendered microporous by, e.g., chromic or permanganate treatment, and then seeded according to known procedures to render them catalytic to electroless metal deposition baths. Alternatively, the polymers may include a filler that is autocatalytic to electroless metal deposition baths and the seeding step may be eliminated, such as is taught in U.S. Patent ~o.
;~ 3,779,758, issued December 18, 1973.
Regarding all of the data below, the test sarnples were precured for one hour at 160C prior to electroless ; metal processing and postbaked for one hour at 160C
following adherent metallization.
Unless otherwise noted, as for Tables II and III, infra, all weight percents herein regarding constituents that enter into the resultant polymer are with respect to the basic liquid mixture, i.e., the weights of other ingredients such as catalysts, solvents and the like are not included. With respect to Tables II and III, all weight percents are based upon the total weight of each : ~ -dc/

10776~3 system given.
Table I sets forth the compositions of the basic liquid mixtures for each of the seven examples described below.

TABLE I

~ CO~PONENT EXAMPLE
; (wt.%) I II III IV V VI VII
carboxylated acrylonitrile butadiene60 60 60 60 61 61 45 epoxy novolac40 40 40 40 -- -- 22 cycloallphatic epoxy-- -- -- -- 25 25 --phenolic novolac-- -- -- -- 14 14 33 The examples of Table II illustrates applications of the invention that result in polymeric substrates that may be rendered microporous according to known methods without prior treatment with a strong organic solvent.
All component concentrations are in weight percents.
Surfsces formed of polymers from mix~ure according to Examples ~ and IV require a seeding step prior to adherent metallization, while polymeric surfaces according to Examples II and III are catalytic to electroless metal deposltion without seedin8.

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5 carboxylated acrylonitrile ~

6 butadiene (B.F. Goodrich CTB ~ 52.3 50.8 54.2 55.7 epoxy novRlac (Dow Chemical 8 DEN 43~ . 34.8 34.0 36.1 37.1 '. 9 .
- 10 flow promoter (Raybo 1 ~ 0.7 0.7 0.7 0.7 11 catalytic filler (PEC-8~ --- 2.6 2.7 ---12 catalyst (solution A*) 12.2 11.9 --- ---13 catalyst (solution B**) --- --- 6.3 6.5 _ *Solution A **Solution B
16 component wt.% com~onentwt.Z
dicyandiamide 11.9 tioyandiamide 21.4 j 17 dimethylformamide 66.7 menthane diamine78.6 silicone resin (Dow~;~ , .
, 18 Corning DC No. 21 ~ 17.8 r~ 19 N,N,N',N'-tetramethyl , butanediamine 3.u .
21 The examples of Table III are directed to the use of 22 mixtures from which polymers yielding surfaces that should 23 be treated with a strong organic solvent prior to oxidation are derived. Polymers from mixtures according to Examples 26 V and VII yield platable surfaces that require seeding, while 27 surfaces of polymers from mixtures according to E~ample VI
28 do not reauire a seeding step prior to adherent metallization.
1 29 Again, all component concentrations are in weight percent.

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I I TABLE III

4 ¦ cycloaliphatic ep (Union ~
I Carbide ERL 423 ~ . 24.0 23.3 ---I carboxylated acrylonitrile 8 I butadiene (B.F. Goodrich CTB ~ 60.0 58.3 44.25 ¦ phenolic novol~c (Monsanto , I ChemicaI P9~ 14.0 13.6 33.2 11 ¦ epoxy novolac (Dow Chemical DEN 438~ 22.1 12 1 latent catalyst (stannous octoate) 2.0 1.9 ___ 3 ¦ catalytic filler (PEC-8~ 2.9 ___ l accelerator (N,~,N',N'-tetramethyl 15 ¦ benzyldiamine) --- --~ 0.45 18 1 Figure 1 is a cured and untouched surface of a 19 1 heterogeneous polymeric substrate according to the invention.

The photomicrograph shows .he surface as it appears under a 21 scanning electron microscope and the conditions indicated.
22 Figure 2 is a photomicrograph of a cured and untouched known 23 surface according to U.S. Patent No. 3,625,758. The surface 24 was prepared by blending masticated acrylonitrile butadiene rubber prepolymer with an epoxy/phenolic mixture. A comparison ~ :

27 of Figures 1 and 2 shows that diphase surfaces resulting from processes according to the lnvention present a more uniiorm 28 appearance than the previously known heterogeneous surfaces.
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~ 1~776~3 Figures 3 and 4, at 2000 and 7000 magnification, respectively, show surfaces of the Figure 1 type follow-ing oxidation in chromic solution according to known procedure, while Figure 5, at 7000 magnification, shows a prior art surface as shown in Figure 2 following the same chromic treatment. As is evident from comparison of Figures 3 and 4 with Figure 5, diphase surfaces according to the present invention result in a relatively well-ordered, honeycomb-like microporous structure following chromic treatment, while the oxidized diphase surface according to U.S. Patent No. 3,6259758 exhibits a much more randomly mlcroroughened and microcracked appearance.
The differences are attributable to the fact that surfaces according to the methods here disclosed include - a low and narrow-range molecular weight unsaturated component, while the diphase polymer surfaces of U.S.
Patent No. 3,625,758 have a very large molecular weight distribution of the dispersed phase rubber, because of the chain length and the dispersion being effected phys-ically.
The unsaturated polymer component of mixtures according to the inventior. and the other components polymerize to yield a dispersed phase rich in polymer having ethylenic unsaturation within a continuous phase or matrix rich in polymer having substantially no ethylenic unsaturation. Because the dispersion is effected by micro phenomena, rather than masticating and blending on a macro scale, the chain length and distribution of the dispersed phase are much more uniform than with previously known heterogeneous surfaces. As indicated by the photomicrographs of the figures, the matrix polymer is much less susceptible than the areas dc/
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. . -- : : .-, . . - - ' : ~ - . . -107~643 rich in unsaturated polymer to oxidative degradation, resulting in a well-ordered microporosity.
Figures 6 and 7 illustrate platable surfaces according to the invention following permanganate treat-ment of a Figure 1 type surface, while Figure 8 illustrates the prior art, Figure 2 type surface follow-ing contacting with a permanganate solution. Again, the honeycomb-like result following oxidative attack of the surfaces of the present invention may be compared to the generally microroughened and microcracked surface resulting from previously preferred hetarogeneous surfaces for adherent metallization in electroless metal deposition baths.
Typical micropore diameters following oxidative attack on the polymeric surfaces described range from about 1000 A to about 45,000 A, with the majority having t diameters in the range of from about 6000 A to about 18,000 A. The depth of penetration varies widely up to about 0.3 mil.
Surfaces resulting from polymers formed from the disclosed preferred embodiments typically produce peel st.engths on the order of ~3 pour.ds per ilLch of width following known electroless metal deposition procedures.
Previously known heterogeneous systems for the electroless deposition of metal thereon would exhibit rather sharp attenuation of peel strengths with increased ~-oxidation treatment time, while metallized polymeric surfaces according to the invention yield a relatively flat peel strength response curve: a five minute oxida-tion treatment yielded a peel strength of about 13 pounds per inch of width and a twenty minute treatment resulted dc/

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in a peel strength of about 15 pounds per inch of width.
Electrolessly metallized diphase surfaces of the sort disclosed are also remarkably heat resistant. There was no evidence of blistering, even on large areas (1" x 3" samples), when articles having metallized poly-meric surfaces according to the invention were dip soldered for 20 seconds at 260C. Repeated application of a soldering iron (up to twelve repetitions) had no blistering effect and evidences an excellent repair capability for such surfaces in printed circuit applica-tions.
Resinous surfaces of the instant invention are widely useful in known electroless metal deposition processes.
For those polymers for which pretreatment prior to activation is suggested, in order to provide polar -~
and strained sites that will be more readily attacked by ~-the oxidizer, contacting with strong organic solvents according to known methods is preferred.
Known oxidizing agents and methods such as chromic, chromic/sulfuric and permanganate treatments may be utilized~
Where a catalytlc filler has been incorporated into the polymeric surface in known fashions, no seeding ~ -step iæ required.
If a seeding process is desired, known processes, such as the typical stannous chloride/palladium chloride methods, may be employed.
- Plating of the instant resinous surfaces may be achieved with a variety of metals according to known procedures, including, but without limitation, copper -~

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(Zeblisky et al U.S. Patent No. 3,095,309, issued June 25, 1963), nickel (Brenner Metal Flnishing, November 1954, pages 68-76), and gold (Brookshire U.S.
Patent No. 2,976,181, issued March 21, 1961).

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A process for producing a diphase polymeric surface for the adherent electroless deposition of metal thereon, the two phases consisting of a dispersed first phase rich in polymer having ethylenic unsaturation and a continuous second phase rich in polymer having substantially no ethylenic unsaturation, said process comprising the steps:
(a) admixing at least two liquid constituents, the first of said constituents comprising a liquid precursor of a solid polymer having ethylenic unsaturation and the second of said constituents comprising a liquid precursor of a solid polymer having substantially no ethylenic unsaturation; and (b) polymerizing the admixture of step (a) to yield a solid, two phase polymerization product comprising a dispersed phase rich in the polymerization product of said first constituent and a continuous phase rich in the polymerization product of said second constituent.

2. A process according to Claim 1, wherein said first constituent is highly polar.

3. A process according to Claim 2, wherein said second constituent has a high functionality.

4. A process according to Claim 3, wherein said first constituent comprises conjugated double bonds.

5. A process according to Claim 4, wherein said first constituent comprises substituted butadiene.

6. A process according to Claim 5, wherein the substituted butadiene comprises acrylonitrile and carboxyl substituents.

7. A process according to Claim 6, wherein said sub-stituted butadiene is carboxyl-terminated acrylonitrile butadiene also having random carboxyl groups along the molecular chain length.

8. A process according to Claim 5, wherein said second constituent comprises at least one member selected from the group consisting of highly functional, liquid precursors of epoxy resins and phenolic resins.

9. A process according to Claim 8, wherein said second constituent comprises at least one member selected from the group of highly functional, liquid precursors of epoxy resins and phenolic resins consisting of epoxy novolac, cycloaliphatic epoxy, and phenolic novolac.

10. A process for producing a diphase polymeric surface for the adherent electroless deposition of metal thereon, the two phases consisting of a dispersed first phase rich in a polymer having ethylenic unsaturation and a continuous second phase rich in a polymer having substantially no ethylenic unsaturation, said process comprising the steps:
(a) forming a liquid mixture comprising two liquid constituents, the first said constituent being a liquid pre-cursor of a solid polymer having ethylenic unsaturation consisting of from about 45 to about 65 percent by weight of a highly polar liquid carboxyl-terminated acrylonitrile-butadiene having carboxyl groups dispersed along the chain length, and the second said constituent being a liquid precursor of a solid polymer having substantially no ethylenic unsaturation consisting of from about 20 to about 40 percent by weight of at least one component selected from the group consisting of liquid novolac resins and liquid cycloaliphatic epoxy resins;
and (b) polymerizing the admixture of step (a) to yield a solid, two phase polymerization product comprising a dispersed phase rich in the polymerization product of said first con-stituent and a continuous phase rich in the polymerization product of said second constituent.

11. An article for the electroless deposition of adherent metal thereon from an electroless metal deposition bath, in which at least a portion of the surface of said article has been coated with a layer of two-phase polymer susceptible to oxidative attack, said polymer comprising a dispersed phase rich in the polymerization product of a first liquid constituent comprising a liquid precursor of a solid polymer having ethylenic unsaturation, and a continuous phase rich in the polymerization product of a second liquid constituent comprising a liquid precursor of a solid polymer having substantially no ethylenic unsaturation.

12. An article for the electroless deposition of adherent metal thereon from an electroless metal deposition bath, in which at least a portion of the surface of said article has been coated with a layer of a two-phase polymer susceptible to oxidative attack, said polymer comprising a dispersed phase rich in the polymerization product of a first liquid constituent comprising a liquid precursor of a solid polymer having ethylenic unsaturation consisting of from about 45 to about 65 percent by weight of a highly polar liquid carboxyl-terminated acrylonitrile-butadiene having carboxyl groups dispersed along the chain length, and a continuous phase rich in the polymer-ization product of a second liquid constituent comprising a liquid precursor of a solid polymer having substantially no ethylenic unsaturation consisting of from about 20 to about 40 percent by weight of at least one component selected from the group consisting of liquid novolac resins and liquid cyclo-aliphatic epoxy resins.