1
                                                                     Exhibit 3.7
                                           to Registration Statement on Form S-4

                         CERTIFICATION OF INCORPORATION
                                       OF
                              RBX-EMPIRE CHEM INC.


       The undersigned incorporator, for the purpose of incorporating
or organizing a corporation under the General Corporation Law of the State of
Delaware, certifies:

       FIRST:    The name of the Corporation is

                            RBX-Empire Chem Inc.

       SECOND:   The address of the Corporation's registered office in the 
State of Delaware is Corporation Trust Center, 1209 Orange Street, in the City
of Wilmington, County of New Castle.  The name of its registered agent at such
address is The Corporation Trust company.

       THIRD:    The purpose of the Corporation is to engage in any lawful act 
or activity for which corporations may be organized under the General
Corporation Law of Delaware.

       FOURTH:   The total number of shares of stock which the Corporation 
shall have authority to issue is One Thousand (1,000) shares of Common Stock,
and the par value of each such share is One Dollar ($1.00)

       FIFTH:    The name and mailing address of the incorporator is Rory A. 
Babich, Paul, Weiss, Rifkind, Wharton & Garrison, 1285 Avenue of the Americas,
New York, New York  10019-6064.

       SIXTH:    Elections of directors need not be by ballot unless the 
By-Laws of the Corporation shall so provide.

       SEVENTH:  The Board of Directors of the Corporation may make By-Laws and 
from time to time may alter, amend or repeal By-Laws.

       EIGHTH:   To the fullest extent permitted by the Delaware General 
Corporation Law as the same exists or may hereafter be amended, a Director of
the Corporation shall not be liable to the Corporation or its stockholders for
monetary damages for breach of fiduciary duty as a Director.

       IN WITNESS WHEREOF, I have signed this Certificate this 24th
day of September, 1990.

                                       /s/   Rory A. Babich 
                               -------------------------------------
                                               Rory A. Babich


   2
                          AMENDMENT OF CERTIFICATE OF
                         INCORPORATION AFTER RECEIPT OF
                               PAYMENT FOR STOCK

                                       OF

                    HOOVER HANES RUBBER CUSTOM MIXING CORP.


                  It is hereby certified that:

                  1.       The name of the corporation (the "Corporation") is
Hoover Hanes Rubber Custom Mixing Corp.

                  2.       The certificate of incorporation of the Corporation
is hereby amended by striking out Article 1 thereof and by substituting in lieu
of said Article the following new Article:

                  FIRST:      The name of the Corporation is

                              Hoover-Hanes Rubber Custom Mixing Corp.

                  3.       The amendment of the certificate of incorporation of
the Corporation herein certified was duly adopted, in accordance with the
provisions of Section 242 of the General Corporation Law of the State of
Delaware.

         Attest:



                                                 /s/   Alan W. Wilkinson      
                                            ----------------------------------
                                            Name:  Alan W. Wilkinson          
                                            Title: Vice President             



    /s/ Christine J. Smith                      
- -------------------------------------
Name:  Christine J. Smith
Title: Secretary


Dated:  December 14, 1990
   3
                      CERTIFICATE OF CHANGE OF REGISTERED

                          OFFICE AND REGISTERED AGENT

                                       OF

                    HOOVER-HANES RUBBER CUSTOM MIXING CORP.


               -------------------------------------------------

The Board of Directors of:

                  HOOVER-HANES RUBBER CUSTOM MIXING CORP. 

a Corporation of the State of Delaware, on this 1st day of October, A.D. 1997,
do hereby resolve and order that the location of the Registered Office of this
Corporation within this State be, and the same hereby is:

1013 Centre Road, in the City of Wilmington, in the County of New Castle,
Delaware, 19805.

         The name of the Registered Agent therein and in charge thereof upon
whom process against the Corporation may be served, is:

CORPORATION SERVICE COMPANY.

                  HOOVER-HANES RUBBER CUSTOM MIXING CORP.

a Corporation of the State of Delaware, does hereby certify that the foregoing
is a true copy of a resolution adopted by the Board of Directors at a meeting
held as herein stated.

         IN WITNESS WHEREOF, said corporation has caused this Certificate to be
signed by Harry L. Schickling, this 1st day of October A.D. 1997.



                                         /s/   Harry L. Schickling           
                                  -------------------------------------------
                                           VP & Secretary
                                          Authorized Officer