Second Amendment to Promissory Note



  
 Exhibit 4.21

 SECOND AMENDMENT TO PROMISSORY NOTE 
 ISSUED FEBRUARY 19, 2009 
 THIS AMENDMENT (the
“Amendment”) is made as of the 30th day of
September, 2010 (the “Effective Date”), by and between Leah Kaplan-Samuels and Leonard Samuels JTWROS, currently residing at 1011 Centennial Road, Penn Valley, PA 10972 (“Holder”) and Dais Analytic Corporation having an office at
11552 Prosperous Drive, Odessa, Florida 33556 (“Maker”). (Each individually referred to herein as “Party” and together as “Parties”). 
 WITNESSETH 
 WHEREAS, on February 19, 2010, Maker issued to Holder an
unsecured promissory note in the principal amount of Two Hundred and Fifty Thousand Dollars ($250,000) (“Note”); and 

WHEREAS, on June 28, 2010 the Parties amended the Note (“First Amendment”) so as to cause the Maturity Date (as
defined in said Note) of the Note to be September 30, 2010; and 
 WHEREAS, the Parties desire to further amend Note
to cause the Maturity Date of said note to be December 31, 2010; and 
 NOW, THEREFORE, in consideration of the
mutual premises, representations, warranties, covenants and agreements contained herein, and intending to be legally bound hereby, the Parties hereto agree as follows: 
  

	1.	The following paragraph of the Note ( as amended) is hereby deleted in its entirety: 


“All payments under or pursuant to this Note shall be made in United States Dollars in immediately available funds to the Holder at
the address of the Holder first set forth above or at such other place as the Holder may designate from time to time in writing to the Maker or by wire transfer of funds to the Holder’s account, as requested by the Holder. The outstanding
principal balance of this Note, together with all accrued and unpaid interest, shall be due and payable in full on September 30, 2010 (the “Maturity Date”) or at such earlier time as provided herein.” 

 

	2.	The following provision is hereby inserted in place of the paragraph deleted pursuant to Section 1 of this Amendment: 


“All payments under or pursuant to this Note shall be made in United States Dollars in immediately available funds to the Holder at
the address of the Holder first set forth above or at such other place as the Holder may designate from time to time in writing 

  

					
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	  	Second Amendment to Promissory Note	  	Samuels/Dais
		  	Issued 2/19/10	  	









 
to the Maker or by wire transfer of funds to the Holder’s account, as requested by the Holder. The outstanding principal balance of this Note, together with all accrued and unpaid interest,
shall be due and payable in full on December 31, 2010 (the “Maturity Date “) or at such earlier time as provided herein.” 
  

	3.	Section 2.3 of the Note, as amended, is hereby deleted in its entirety and the following provision shall be inserted in place thereof: 


“Section 2.3. Additional Remedy Upon Non-Payment. If this Note is not paid in full on or before December 31, 2010, the
Holder shall be permitted, at its sole option and in addition to its other remedies hereunder, to convert the principal and interest outstanding under this Note into any debt, equity or equity-linked security issued by the Maker in connection with
any capital-raising issuance after the date hereof and prior to the date this Note is paid in full on the terms and conditions of such offering, if any, it being understood that (i) nothing in this Section 2.3 shall be deemed to prohibit
the Maker from prepaying the Note pursuant to Section 1.2 hereof and (ii) in connection with any such conversion, the security issued to the Holder shall contain customary 9.9% beneficial ownership limitations in form and substance
satisfactory to the Holder.” 
  

	4.	All other terms and conditions of the Note shall remain unchanged and in full force and effect. 


IN WITNESS WHEREOF, the Parties have caused this Amendment to be executed by their duly authorized respective representatives as
of the date first written above. 
  

			
	DAIS ANALYTIC CORPORATION
	
	 By: /s/ Timothy N. Tangredi

	 Name:
	 	Timothy N. Tangredi
	 Title:
	 	President and Chief Executive Office
	
	HOLDERS
	
	/s/ Leah Kaplan-Samuels
	 Leah Kaplan-Samuels

	
	/s/ Leonard Samuels
	 Leonard Samuels



  

					
	 Page 2 of 2
	  	Second Amendment to Promissory Note	  	Samuels/Dais
		  	Issued 2/19/10